A biochemist would most likely study what ?

Answer:

It dissolves into the water

Na₂SO₄ + H₂O → 2Na₊_{aq} + SO₄²-_{aq}

Hope this helps :)

Have a great day !

5INGH

Explanation:

Answer:

[tex]\boxed{\text{bp =100.106 }^{\circ}\text{C; fp = -0.387 }^{\circ}\text{C; bp =101.68 }^{\circ}\text{C}}[/tex]

Explanation:

Q8. Boiling point

Data:

m(KOH) = 53.1 g

m(H₂O) = 9.10 kg

    K_b = 0.512 °C·kg·mol⁻¹

Calculations:

(a) Moles of KOH

[tex]\text{Moles of KOH} = \text{53.1 g KOH} \times \dfrac{\text{1 mol KOH}}{\text{56.11 g KOH}} = \text{0.9464 mol KOH}[/tex]

(b) Molal concentration

The formula for molal concentration (b) is

[tex]b = \dfrac{\text{moles of solute}}{\text{kilograms of solvent}} = \dfrac{0.9464}{9.1} = \text{0.104 mol/kg}[/tex]

(c) Boiling point elevation

The formula for the boiling point elevation ΔTb is

[tex]\Delta T_{b} = iK_{b}b[/tex]

i is the van’t Hoff factor: the number of moles of particles you get from a solute.

For KOH,

 KOH(s)  ⟶     K⁺(aq) + OH⁻(aq)

1 mol KOH ⟶ 2 mol particles   i = 1

[tex]\Delta T_{b} = 2 \times 0.512 \times 0.104 = \text{0.106 }^{\circ}\text{C}[/tex]

(d) Boiling point

[tex]T_{b} = T_{b}^{\circ} + \Delta T_{b} = 100.000 + 0.106 = \text{100.106 }^{\circ}\text{C}[/tex]

Q9. Freezing point  

[tex]\Delta T_{f} = iK_{f}b = 2 \times 1.86 \times 0.104 = \text{0.387 }^{\circ}\text{C}\\\\T_{f} = T_{f}^{\circ} - \Delta T_{f} = 0.000 - 0.387 = \text{-0.387 }^{\circ}\text{C}[/tex]

Q10. Boiling point

[tex]\text{Kilograms of phenol} = 645 \times \dfrac{1}{1000} = \text{0.645 kg phenol}\\\\b = \dfrac{0.910}{0.645} = \text{1.411 mol/kg}\\\\\Delta T_{b} = 1\times 1.19 \times 1.411 = \text{1.68 }^{\circ}\text{C}\\T_{b} = 100.00 + 1.68 = \text{101.68 }^{\circ}\text{C}[/tex]

Answer:

ti make gas to make things work and for stalk on the market

Explanation:

Answer:

n = 5.

Explanation:

How many carbon atoms in total in this straight-chain hydrocarbon?

The prefix of the IUPAC name of a hydrocarbon (the part before -ane) shows the number of carbon atoms on the longest carbon chain.

[tex]\begin{array}{c|c}\text{Number of Carbon}\\ \text{atoms in backbone} & \text{Prefix}\\[-0.5em]\multicolumn{2}{c}{\rule{5cm}{0.5pt}}\\1& \text{meth-} \\ 2&\text{eth-} \\ 3&\text{prop-}\\4 & \text{but-}\\5 & \text{pent-} \\ 6 & \text{hex-} \\ 7 & \text{hept-} \\8 & \text{oct-}\\ \dots & \dots\end{array}[/tex].

Hence the structure:

[tex]\text{CH}_3\text{-CH}_2\text{-CH}_2\text{-CH}_2\text{-CH}_2\text{-CH}_2\text{-CH}_3[/tex].

All the [tex]\text{-CH}_2\text{-}[/tex] in the formula might look redundant. "[tex]\text{CH}_2[/tex]" appears five times in a row and may be condensed into [tex](\text{CH}_2)_5[/tex]. Hence the condensed formula:

[tex]\text{CH}_3\text{-}{(\text{CH}_2)_{\bf5}\text{-CH}_3[/tex].

Therefore [tex]n = 5[/tex].

Answer:

n+5 so the correct answer is b) 5

Explanation:

just did review on edge

The formula of aluminum nitride is AlN

the molar mass of Al = 27 amu

the molar mass of N = 14

(1 x 27) + (1 x 14)

= 27 + 14

= 41 amu

Answer:

Pd(O₂CCH₃)₂

Explanation

Answer:

Pd(O2CCH3)2

Pd2C8H12O8

Explanation:

Given:

% Pd = 47.40

% O = 28.50

% C = 21.40

% H = 2.69

To determine:

Molecular formula of the compound containing Pd, O, C and H

Calculation:

Let the mass of the compound = 100g

Therefore based on the % compositions:

Mass of Pd = 47.40g

Mass of O = 28.50g

Mass of C = 21.40g

Mass of H = 2.69g

Atomic mass of Pd = 106.42 g/mol

Atomic mass of O = 15.99 g/mol

Atomic mass of C = 12.01 g/mol

Atomic mass of H = 1.00 g/mol

[tex]moles\ of\ Pd = \frac{47.40g}{106.42g/mol} =0.4454[/tex]

[tex]moles\ of\ O = \frac{28.50g}{15.99g/mol} =1.782[/tex]

[tex]moles\ of\ C = \frac{21.40g}{12.01g/mol} =1.782[/tex]

[tex]moles\ of\ H= \frac{2.69g}{1.00g/mol} =2.690[/tex]

Ratio:

[tex]Pd = \frac{0.4454}{0.4454} = 1.00\\\\O = \frac{1.782}{0.4454} = 4.00\\\\C = \frac{1.782}{0.4454} = 4.00\\\\H = \frac{2.690}{0.4454} = 6.039[/tex]

The empirical formula is : PdO4C4H6

Molecular formula = n(Empirical formula)

If n = 1

Molecular formula = PdO4C4H6 i.e. Pd(O2CCH3)2

If n= 2

Molecular formula = 2(PdO4C4H6)= Pd2O8C8H12

Answer:

The volume of hydrogen gas produced will be approximately 50.7 liters under STP.

Explanation:

Relative atomic mass data from a modern periodic table:

Magnesium is a reactive metal. It reacts with hydrochloric acid to produce

The chemical equation will be something like

[tex]\rm ?\;Mg\;(s) + ?\;HCl \;(aq)\to ?\;H_2 \;(g)+ [\text{Formula of the Salt}][/tex],

where the coefficients and the formula of the salt are to be found.

To determine the number of moles of [tex]\rm H_2[/tex] that will be produced, first find the formula of the salt, magnesium chloride.

Magnesium is a group 2 metal. The oxidation state of magnesium in compounds tends to be +2.

On the other hand, the charge on each chloride ion is -1. Each magnesium ion needs to pair up with two chloride ions for the charge to balance in the salt, magnesium chloride. The formula for the salt will be [tex]\rm MgCl_2[/tex].

[tex]\rm ?\;Mg\;(s) + ?\;HCl\;(aq) \to ?\;H_2 \;(g)+ ?\;MgCl_2\;(aq)[/tex].

Balance the equation. [tex]\rm MgCl_2[/tex] contains the largest number of atoms among all species in this reaction. Start by setting its coefficient to 1.

[tex]\rm ?\;Mg\;(s) + ?\;HCl\;(aq) \to ?\;H_2 \;(g)+ {\bf 1\;MgCl_2}\;(aq)[/tex].

The number of [tex]\rm Mg[/tex] and [tex]\rm Cl[/tex] atoms shall be the same on both sides. Therefore

[tex]\rm {\bf 1\;Mg}\;(s) + {\bf 2\;HCl}\;(aq) \to ?\;H_2 \;(g)+ {1\;\underset{\wedge}{Mg}\underset{\wedge}{Cl_2}}\;(aq)[/tex].

The number of [tex]\rm H[/tex] atoms shall also conserve. Hence the equation:

[tex]\rm {1\;Mg}\;(s) + {2\;\underset{\wedge}{H}Cl}\;(aq) \to {\bf 1\;H_2 \;(g)}+ {1\;MgCl_2}\;(aq)[/tex].

How many moles of HCl are available?

[tex]M(\rm HCl) = 1.008 + 35.45 = 36.458\;g\cdot mol^{-1}[/tex].

[tex]\displaystyle n({\rm HCl}) = \frac{m(\text{HCl})}{M(\text{HCl})} = \rm \frac{165.0\;g}{36.458\;g\cdot mol^{-1}} = 4.52576\;mol[/tex].

How many moles of Hydrogen gas will be produced?

Refer to the balanced chemical equation, the coefficient in front of [tex]\rm HCl[/tex] is 2 while the coefficient in front of [tex]\rm H_2[/tex] is 1. In other words, it will take two moles of [tex]\rm HCl[/tex] to produce one mole of [tex]\rm H_2[/tex]. [tex]\rm 4.52576\;mol[/tex] of [tex]\rm HCl[/tex] will produce only one half as much [tex]\rm H_2[/tex].

Alternatively, consider the ratio between the coefficient in front of [tex]\rm H_2[/tex] and [tex]\rm HCl[/tex] is:

[tex]\displaystyle \frac{n(\text{H}_2)}{n(\text{HCl})} = \frac{1}{2}[/tex].

[tex]\displaystyle n(\text{H}_2) = n(\text{HCl})\cdot \frac{n(\text{H}_2)}{n(\text{HCl})} = \frac{1}{2}\;n(\text{HCl}) = \rm \frac{1}{2}\times 4.52576\;mol = 2.26288\;mol[/tex].

What will be the volume of that many hydrogen gas?

One mole of an ideal gas occupies a volume of 22.4 liters under STP (where the pressure is 1 atm.) On certain textbook where STP is defined as [tex]\rm 1.00\times 10^{5}\;Pa[/tex], that volume will be 22.7 liters.

[tex]V(\text{H}_2) = \rm 2.26288\;mol\times 22.4\;L\cdot mol^{-1} = 50.69\; L[/tex], or

[tex]V(\text{H}_2) = \rm 2.26288\;mol\times 22.7\;L\cdot mol^{-1} = 51.37\; L[/tex].

The value "165.0 grams" from the question comes with four significant figures. Keep more significant figures than that in calculations. Round the final result to four significant figures.

Answer:

The relationship shown is cordial relationship

Yes it’s corrrct I swear

At 98.66 kPa and 20°C nitrogen has a solubility in water of .018 g/L. At 82.66 kPa and 20°C, it’s solubility is 015 g/L. Nitrogen obey the gas pressure solubility law.

Henry's Law is a gas law states that the solubility of a gas in liquid is directly proportional to the pressure of that gas.

It is expressed as:

[tex]P_{i} = K_{H}\ X_{i}[/tex]

where,

[tex]P_{i}[/tex] = Partial pressure of the gas

[tex]X_{i}[/tex] = Mole fraction of gas

[tex]K_{H}[/tex] = Henry's Law constant

Ammonia, Hydrogen halide (like Hydrochloric acid) and Hydrogen sulfide these gases does not obey Henry's Law.

Thus from the above conclusion we can say that At 98.66 kPa and 20°C nitrogen has a solubility in water of .018 g/L. At 82.66 kPa and 20°C, it’s solubility is 015 g/L. Nitrogen obey the gas pressure solubility law.

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Answer:

The number of protons of the Pb is 82.

The number of electrons of the Pb²⁺ is 80.

Explanation:

Each chemical element is characterized by the number of protons in its nucleus, which is called the atomic number Z.  

The atomic number is used to classify the elements within the periodic table of the elements. In it, you can read in the upper left.  In this case, the lead Pb has an atomic number of 82. This indicates that the number of protons of the Pb²⁺ is 82.

In every electrically neutral atom the number of protons in the nucleus is equal to the number of electrons in their orbitals. But in this case it is a cation, that is, it is a positively charged ion. A cation is formed when electrons are lost (which have a negative charge), thus acquiring the positive charge ion. In this case then, Pb²⁺ indicates that the cation has a +2 charge. So this means that 2 electrons have been lost.  So, if it were electrically neutral, the lead Pb would have 82 electrons, but with the loss of two of its electrons, the number of electrons of the Pb²⁺ is 80.

There are 82 protons and 80 electrons in one Pb²⁺ ion. Lead (Pb) has an atomic number of 82.

The atomic number of an element represents the number of protons in its nucleus. Since lead (Pb) has an atomic number of 82, it means that a neutral lead atom has 82 protons.

When the Pb²⁺ ion is formed, it means that the atom has lost two electrons. The +2 charge indicates that the atom now has two more protons than electrons. Since electrons have a negative charge, losing two of them results in a net positive charge on the ion.

Since a neutral lead atom has 82 electrons, subtracting two electrons from it gives us 80 electrons in the Pb²⁺ ion. However, the number of protons remains the same at 82. The loss of electrons creates a positive charge, and the number of protons determines the element's identity.

In summary, the Pb²⁺ ion has 82 protons and 80 electrons. The 2+ charge indicates the loss of two electrons, resulting in a net positive charge on the ion.

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Answer:

16.4 L

Explanation:

we can use the combined gas law equation that gives the relationship among volume, temperature and pressure conditions of gases.

P1V1/T1 = P2V2/T2

STP conditions are standard temperature and pressure conditions

P1 is standard pressure = 1 atm , T1 is standard temperature = 273 K

and V1 is the volume

P2 is pressure, T2 is temperature and V2 is volume at the second instance

temperature is in kelvin scale,

512 ° + 273 = 785 K

substituting the values in the equation

1 atm x 10.0 L / 273 K = 1.75 atm x V / 785 K

V = 16.4 L

new volume is 16.4 L

Answer:

Star A

Explanation:

Based on the information provided, we can determine that the color of a star is related to its surface temperature, with hotter stars appearing more blue and cooler stars appearing more red.

Looking at the graph, we can see that the stars along the left side of the graph (with negative values on the x-axis) are hotter than the stars on the right side of the graph. Therefore, Star A, which has coordinates of 20,000 and -4, is hotter than Star B, which has coordinates of 2,500 and -4.

Comparing the coordinates of Star A to the lines representing the different types of stars, we can see that it falls on the line for main sequence stars. Main sequence stars are typically white or blue-white in color, so Star A is most likely to be blue.

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Star D is most likely to be blue, as it has a high surface temperature compared to the other stars listed (7,000 degrees Celsius) and aligns with the typical characteristics of blue stars.

The color of a star is closely related to its surface temperature. Hotter stars tend to appear bluer, while cooler stars appear redder.

Looking at the provided coordinates for the stars:

- Star A has coordinates (20,000, -4), indicating a high surface temperature.

- Star B has coordinates (2,500, -4), indicating a lower surface temperature.

- Star C has coordinates (5,000, 2), indicating a moderate surface temperature.

- Star D has coordinates (7,000, 4), indicating a relatively high surface temperature.

Among the given stars, Star A and Star D have the highest surface temperatures, making them more likely to appear blue. However, between these two, Star D has an even higher temperature, making it the most likely to be blue. Therefore, Star D is the star most likely to be blue.

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Answer:

D.

Explanation:

Nuclear energy does not have greenhouse gas emissions. The emissions produced by nuclear fission plants are similar to renewable energy sources.The generation of power using nuclear energy does not affect air quality thus providing a clean source of energy.Nuclear energy originates from radioactive material which are harmful to living organisms.

Answer:

D. risk from radioactive material; benefit of obtaining low-cost energy

Explanation:

I just took the test. Ap*x

Answer:

[tex]\boxed{\text{1. 0.47 mol; 2. 0.046 mol; 3 (a) 11.6 mol, 15.4 mol, (b) 2.31 mol, 3.08 mol, 0.770 mol}}[/tex]

Explanation:

1. Moles of Na

(a) Balanced equation

2Na + 2H₂O ⟶ 2NaOH + H₂

(b) Calculation

You want to convert moles of H₂ to moles of Na

The molar ratio is 2 mol Na:1 mol H₂

Moles of Na  = 4.0 mol H₂ × (2 mol Na/1 mol H₂) = 8.0 mol Na

You need [tex]\boxed{ \text{8.0 mol of Na}}[/tex] to form 4.0 mol of H₂.

2. Moles of LiCl

(a) Balanced equation

2LiBr + Cl₂⟶ 2LiCl + Br₂

(b) Calculation

You want to convert moles of LiBr to moles of LiCl

The molar ratio is 2 mol LiBr:2 mol LiCl

Moles of LiCl  = 0.046 mol LiBr × (2 mol LiCl/2 mol LiBr) = 0.046 mol LiCl

The reaction will produce [tex]\boxed{ \text{0.046 mol of LiCl}}[/tex].

3. Combustion of propane

C₃H₈ +5O₂ ⟶ 3CO₂ +4H₂O

(a) Moles of CO₂ and H₂O

Moles of CO₂ = 0.647 mol O₂ × (3 mol CO₂/1 mol C₃H₈) = 11.6 mol CO₂

Moles of H₂O = 3.85 mol O₂ × (4 mol CO₂/1 mol C₃H₈) = 15.4 mol H₂O

The reaction produces [tex]\boxed{ \text{11.6 mol of CO}_{2}}[/tex] and [tex]\boxed{ \text{15.4 mol of H}_{2}\text{O}}[/tex].

(b) Moles from O₂

Moles of CO₂ = 3.85 mol O₂ × (3 mol CO₂/5 mol O₂) = 2.31 mol CO₂

Moles of H₂O = 3.85 mol O₂ × (4 mol CO₂/5 mol O₂) = 3.08 mol H₂O

Moles of C₃H₈ = 3.85 mol O₂ × (1 mol C₃H₈/5 mol O₂) = 0.770 mol C₃H₈

The reaction produces [tex]\boxed{ \text{2.31 mol}}[/tex] of CO₂, [tex]\boxed{ \text{3.08 mol}}[/tex] of H₂O, and consumes [tex]\boxed{ \text{0.770 mol}}[/tex] of C₃H₈.

The sharing electrons between atoms indicates an ionic bond is FALSE.

I hope this helps

The sharing of electrons between atoms indicates an ionic bond is option B. False.

Hence, the sharing of electrons between atoms indicates an ionic bond is False.

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The way the brain works is that you learn from repetition, the more you do something the better you get at it. So the more you review the first 20 elements on the periodic table, the more often you'll be able to remember it until you're about to recount them without hardly thinking of it.

My advice to you is to grab some pieces of paper. Cut them up into sixths until you have twenty of them, then write down on each smaller piece of paper the numbers 1 up to 20. Then on the other side of the paper, write down the element. Do this in accordance to their position on the periodic table. Then spend some time guessing as to what element is on the other side of the numbered paper. You'll start guessing, "the first element is Hydrogen. The second element is Helium." And so on. Rinse and repeat until you're able to guess the element depending on its placement on the periodic table. Good luck!

Happy. – H Hydrogen

Henry – He Helium

Lives – Li Lithium

Beside – Be Beryllium

Born – B Boron

Cottage – C Carbon

Near – N Nitrogen

Our – O Oxygen

Friend – F Fluorine.

Nelly – Ne Neon

Nancy – Na Sodium

Mg – Mg Magnesium

Allen – Al Aluminum

Silly – Si Silicon

Patrick – P Phosphorus

Stays – S Sulphur

Close – Cl Chlorine

Arthur – Ar Argon

Kisses – K Potassium

Carrie – Ca Calcium

Hope this helps :)

Difference Between Chemical and Physical Weathering.

Weathering processes crack, wear away, and weaken rocks.

While physical weathering breaks down a rock's physical structure, chemical weathering alters a rock's chemical composition.

Final answer:

Physical weathering is the process of breaking down rocks without changing their chemical composition, while chemical weathering involves chemical reactions that alter the composition of rocks. Physical weathering can occur through forces like freeze-thaw cycles, while chemical weathering can happen through processes like oxidation and hydration.

Explanation:

Physical weathering, also known as mechanical weathering, is the process of breaking down rocks and minerals into smaller pieces without changing their chemical composition. This occurs through physical forces such as freeze-thaw cycles, temperature changes, abrasion, and pressure.

Chemical weathering is the process in which rocks and minerals are broken down by chemical reactions that alter their composition. This can happen through processes such as oxidation, hydration, hydrolysis, and carbonation. Chemical weathering can result in the formation of new minerals and alteration of the rock's structure.

An example of physical weathering is when water freezes in cracks in a rock, causing it to expand and eventually crack. An example of chemical weathering is the reaction between water and limestone, which leads to the formation of caves and sinkholes.

Answer:

Explanation:

Givens

P = 1.25 atm

V = 5.4 L

P1 = 3 atm

V1 = ??

Formula

The basic formula is P*V = P1 * V1

Solution

1.25 * 5.4 = 3 * V1

6.75 = 3*V1

6.75 /3 = 3*V1/3

2.25 = V1

Answer:

It is necessary for contracting muscles, forming and strengthening bones and teeth, conducting nerve impulses throughout the body, clotting blood, maintaining a normal heartbeat

Answer:

calcium is essential for living organisms.  it is vital for the body's good health.

Bone health

Vitamin D is helps the body absorb and retain calcium

it helps with muscle contraction

helps in normal blood coagulation (clotting)

it is a co-factor for many enzymes

helps the smooth muscles that surrounds the blood vessels; causes it to relax

Explanation:

Answer:

organism, population, community, ecosystem

Explanation:

Answer: Organism, Population, Community, and lastly Ecosystem

Explanation: Organism is one living thing. Population is a group of organisms of one type that live together. Communities are populations that live together in an area. Ecosystem is a community with its non living surroundings.

Hope this helps :)

Answer:

3+

Explanation:

Boron belongs to the 3rd group, the Boron family on the periodic table. It has an atomic number of 5. For neutral atoms of Boron, we have 5 electrons in them.

All atoms lose or gain electrons in order to achieve a perfect noble gas configuration which would give them stability. Noble gases are known to be stable and unreactive.

For Boron, it would readily want to lose 3 electrons so as to mimic a Helium, He atom. Helium is the first element in the noble gas series.

When Boron loses 3 electrons, a net charge of 3+ is left on the atom of Boron.

Answer:

General formula of the hydrate XY.5H₂O

Explanation:

The general formula of a hydrate is given by; XY.nH₂O

Where n is the number of water of crystallization;

n = Moles of H₂O/Moles of XY

  = 0.050 Mol/0.00998 moL

  = 5.01

  ≈ 5

Therefore, the generalized formula of the hydrate is XY.5H₂O

Answer:

2(Al 3+) + 3/2 O2 ---> Al2O3

Answer:

The correct coefficients for the following reaction:

[tex]4Al+3S2\rightarrow 2Al_2S_3[/tex]

Explanation:

[tex]Al+S2\rightarrow Al_2S_3[/tex]

Given reaction is not balanced.

According to Law of conservation of mass states that mass can neither be created nor be destroyed but it can only be transformed from one form to another form.  

This also means that total mass on the reactant side must be equal to the total mass on the product side.

Stoichiometric coefficient is the numeral written before the chemical compound in a balance chemical reaction.

[tex]4Al+3S2\rightarrow 2Al_2S_3[/tex]

vertical colums tell the valence and the horozontal rows tell the amount of rings that the electrons circle in.

It is easy to find this by simply looking at the Group # (these are the column numbers).

Elements in Group 1 all have 1 electron in their valence shell, Elements in group 2 have 2 and so on...

If you mean how many shells there are then look at the Period # this is the horizontal groups) the Period # corresponds with the number of electron shells.

Elements in Period 2 have 2 electron shells, elements in Period 3 have 3 and so on...

To determine the valency of an element, one must consider its position in the periodic table and its electron configuration.

The valency of an element is the number of electrons it can lose, gain, or share when forming chemical compounds.

1. Main Group Elements (Groups IA to VIIIA, except He):

- Groups IA and IIA: The group number gives the valency. For example, elements in Group IA (e.g., Na) have a valency of 1, and those in Group IIA (e.g., Mg) have a valency of 2.

- Groups IIIA to VIA: The valency can be determined by subtracting the group number from the total number of valence electrons (8 for nonmetals, 18 for noble gases). For example, Nitrogen (Group VA) has 5 valence electrons, so its valency is 8 - 5 = 3.

- Halogens (Group VIIA): These elements have 7 valence electrons, so they have a valency of 1 (since they tend to gain one electron to achieve a full valence shell).

- Noble Gases (Group VIIIA): These elements typically have a valency of 0 because they have a full valence shell.

2. Transition Metals (Groups IB to VIIIB):

- These elements can exhibit multiple valencies, often corresponding to different oxidation states. Commonly, the valency is one or two less than the group number. For example, Iron (Fe, Group VIIIB) can have valencies of 2 or 3.

3. Inner Transition Metals (Lanthanides and Actinides):

- These elements also exhibit multiple valencies, usually +3 or +4.

4. Metalloids (B, Si, Ge, As, Sb, Te):

- Their valency can vary depending on the compound they form. For example, Silicon (Si) can have valencies of 4 or -4.

To ace chemistry exams, consider the following strategies:

- Understand Concepts: Ensure you have a solid grasp of the fundamental concepts rather than just memorizing facts.

- Practice Problems: Work through a variety of problems, especially those from past exams if available.

- Study Regularly: Spread out your study sessions over time rather than cramming the night before.

- Organize Study Material: Use flashcards, charts, and diagrams to help visualize and remember information.

- Form Study Groups: Discussing concepts with peers can provide new insights and clarify misunderstandings.

- Ask for Help: If you're struggling with certain topics, don't hesitate to ask teachers or tutors for clarification.

- Stay Healthy: Get enough sleep, eat well, and stay hydrated to ensure your brain is functioning optimally.

- Manage Time During the Exam: Allocate your time wisely, answering easier questions first and returning to more challenging ones later.

By applying these strategies and understanding the principles behind chemical reactions and the periodic table, you can improve your performance in chemistry exams.

Answer:

I think it is high and electric

Explanation:

Answer:

strong conductivity of plasma allows it to act and react as electric and magnetic fields.

How many were there to start off with?

The custodian receives 5 slices of pie, 7 cups of orange juice, and 11 doughnut holes as leftovers.

To calculate the leftovers for the custodian, we must first calculate how many items the students consume and subtract that from the total provided by the caterer:

Answer:

It raises the boiling point and lowers the freezing point.

Explanation:

It is used as antifreeze in the cooling circuits of internal combustion engines, that is, it is used to reduce the melting point of the solution.

By adding ethylene glycol I'm not only bringing the melting point to -13°C, but the boiling point of ethylene glycol is 197°C.

since these substances not only lower the freezing point but also increase the boiling point, they are also called a colligative agent

Answer:

The correct option is A) It raises the boiling point and lowers the freezing point.

Explanation:

Consider the provided information.

Ethylene glycol is often used for convective heat transfer.

The freezing point of pure ethylene glycol is about −12° C and boils at 198° C.

Due to the higher boiling point and antifreeze properties, it is used in a vehicle’s radiator.

Therefore, the correct option is A) It raises the boiling point and lowers the freezing point.

liquid is fluid in motion, needing to be contained. while a solid state of matter is as such and won't run down the cabinet

Answer:

When an element or substance is in a liquid state, the particles are joined by less attractive forces than in solids, for this reason the particles of a liquid can move freely.For this reason the particles of a liquid can move freely and need a recipient that contains them .

Liquids have a defined volume but with a variable shape, this means that liquids adopt the shape of the container but always occupy the same space

For example, if we have 4 L of water in a round container, its shape is round and now we put the water in a square container, its shape is now square but its volume is still 4 L (it continues to occupy the same space)

Answer:

22.3 mol

Explanation:

He is in STP conditions

This means that it is in standard conditions of temperature and pressure, under these conditions the pressure has a value of 1 atm and the temperature has a value of 273 K

To calculate the number of moles in 500L of He gas we use the ideal gas equation

[tex]P.V=n.r.T\\r(constant of ideal gases)= 0.082\frac{atm.L}{K.mol}[/tex]

We cleared the moles (n)

[tex]P.V=nr.T\\\frac{P.V}{r.T}=n\\\frac{1atm.500L}{0.082atm.L/K.mol.273K}=n\\\\22.3 mol=n[/tex]

The number of moles in 500 L of He gas at STP 22.3 mol

The number of moles in 500 L of helium (He) gas at standard temperature and pressure (STP) is approximately 22.32, based on the standard molar volume concept of chemistry.

The number of moles in 500 L of He gas at STP can be determined using the standard molar volume, which states that at standard temperature and pressure (STP), one mole of any ideal gas occupies a volume of 22.4 L. In this case, to find the moles of helium gas, you would use the formula n = V/V_m, where n is the number of moles, V is the volume of the gas, and V_m is the molar volume at STP.

Substituting the given values into the equation: n = 500 L/22.4 L/mol = 22.32 moles.So, there are approximately 22.32 moles of helium gas in 500 L at STP.

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Answer:

3

Explanation:

Since the atom has three electrons, it has a -3 electrical charge. Since atoms are neutral, 3 protons are needed to get the charge back to 0.

An atom maintains a neutral charge when it has an equal number of protons and electrons. Therefore, an atom with three electrons will have three protons. This principle is integral to the formation of ions when atoms gain or lose electrons.

An atom is characterized by having an equal number of protons and electrons, thus maintaining a neutral charge. Protons carry a positive charge and electrons a negative one. Keeping in mind that a neutral atom has an equal number of both, if an atom has three electrons, it also has three protons.

In Chemistry, we know that atoms are neutral if they contain the same number of positively charged protons and negatively charged electrons. When the counts of these particles are unequal, the atom is electrostatically charged and is called an ion. This charge is calculated as: Atomic charge = number of protons - number of electrons.

For instance, if a neutral sodium atom (Z = 11) with 11 electrons loses one, it forms a cation with a 1+ charge (11 - 10 = 1+). Conversely, a neutral oxygen atom (Z = 8) gaining two electrons becomes an anion with a 2- charge (8 - 10 = 2-).

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