Answer:
C. In every area of work.
Explanation:
(Apex)
In every area of work, chemicals are found. Hence, option C is correct.
What are chemicals?A chemical is any substance that has a defined composition.
In every area of work, chemicals are found.
Some commonly used workplace chemical hazards include:
Acids.Caustic substances.Cleaning products such as toilet cleaners, disinfectants, mildew remover and chlorine bleach.Glues.Heavy metals, including mercury, lead, cadmium, and aluminium.Paint.Pesticides.Petroleum products.Learn more about the chemicals here:
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What is the volume of 1.9 moles of chlorine gas (Cl2) at 298 K and 1.3 atm?
A. 12 L
B. 28 L
C. 36 L
D. 81 L
The answer is:
The correct option is option C.
[tex]V=36L[/tex]
Why?To calculate the volume of the gas sample, we need to use the Ideal Gas Law, this equation is used to relate the pressure, the volume, the mass and the temperature of a gas, so, we can isolate the volume from it.
The Ideal Gas Law equation is equal to:
[tex]PV=nRT[/tex]
Where,
P is the pressure (in atm)
V is the volume (in liter)
n is the mass of the gass (in mole)
T is the temperature of the gass (absolute temperature)
So, from the statement we know that:
[tex]Pressure=1.3atm\\Temperature=298K\\n=1.9moles\\R=0.082057\frac{L.atm}{mol.K}[/tex]
Then, substituting and calculating we have:
[tex]PV=nRT\\\\V=\frac{nRT}{P}=\frac{1.9moles*0.082057\frac{L.atm}{mol.K}*298K}{1.3atm}=35.74L[/tex]
Now, rounding to the nearest whol number we have that the volume is equal to 36 L.
Hence, the correct option is option C.
Have a nice day!
What type of matter is 500 grams of silver combined with gold?
Answer:
A Mixture of two elements
Explanation:
what is the molecular formula of ferrous nitrate and ferric nitrate
How does science use models to gain a better understanding of concepts?
Answer:In science, a model is a representation of an idea, an object or even a process or a system that is used to describe and explain phenomena that cannot be experienced directly. Models are central to what scientists do, both in their research as well as when communicating their explanations.
Explanation:
Determine the enthalpy change of the following reaction: 2KClO3 -> 2KCl + 3O2
Given enthalpies:
KClO3: -391.4 kJ/mol
O2: 0 kJ/mol
KCl: -436.7 kJ/mol
Answer:
- 90.6 kJ/mol.
Explanation:
The enthalpy change of the reaction (ΔHrxn) is the difference between the sum of heat of formation of products and reactants.ΔHrxn = ∑ΔHf(products) - ∑ΔHf(reactants)
For the reaction: 2KClO₃ → 2KCl + 3O₂,
∴ ΔHrxn = ∑ΔHf(products) - ∑ΔHf(reactants)
∴ ΔHrxn = [(2*ΔHf(KCl)) + (3*ΔHf(O₂))] - [(2*ΔHf(KClO₃))] = [(2*(- 436.7 kJ/mol)) + (3*(0)] - [(2*(- 391.4 kJ/mol)] = [- 873.4 kJ/mol] - [- 782.8 kJ/mol] = - 90.6 kJ/mol.
The enthalpy change of the reaction 2KClO3 -> 2KCl + 3O2 is calculated by subtracting the sum of the enthalpies of the reactants from the sum of the enthalpies of the products. The calculation results in an enthalpy change of 90.6 kJ, meaning the reaction is endothermic.
Explanation:The enthalpy change of the reaction can be calculated by subtracting the sum of the enthalpies of the reactants from the sum of the enthalpies of the products. This is also known as Hess's law.
In this reaction, the reactants are 2 moles of KClO3 and the products are 2 moles of KCl and 3 moles of O2. Hence, the enthalpy of the reaction can be calculated as follows:
Enthalpy change = [2 * (-391.4 kJ/mol)] - [2 * (-436.7 kJ/mol) + 3 * 0 kJ/mol]
= (-782.8 kJ) - (-873.4 kJ)
= 90.6 kJ
Therefore, the enthalpy change of this reaction is 90.6 kJ. If the enthalpy change is positive, the reaction is endothermic meaning it absorbs heat from the surroundings.
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what is the specific heat of a substance that absorbs 2.5×10^3 joules of heat when a sample of 1.0 ×10^4g of the substance increases in temperature from 10°c to 70°c?
Answer:
0.004167 J/g°C is the specific heat of a substance.
Explanation:
[tex]Q=m\times c\times \Delta T[/tex]
[tex]Q=m\times c\times (T_{2}-T_1)[/tex]
Where:
Q = heat absorbed(positive) or released (negative)
m = Mass of substance
c = specific heat of a substance
[tex]T_1[/tex] = Initial temperature
[tex]T_2[/tex] = Final temperature
We have:
m = [tex]1.0\times 10^4 g[/tex]
c = ? , [tex]T_1=10^oC,T_2=70^oC[/tex]
Q = [tex]2.5\times 10^3 J[/tex]
[tex]2.5\times 10^3 J=1.0\times 10^4 g\times c\times (70^oC-10^oC)[/tex]
[tex]c=\frac{2.5\times 10^3 J}{1.0\times 10^4 g\times (70^oC-10^oC)}[/tex]
[tex]c=0.004167 J/g^oC[/tex]
0.004167 J/g°C is the specific heat of a substance.
An unknown substance is a white solid at room temperature and has a melting point of 78 °C. Which of the following substances is most likely to be the identity of the unknown sample?
A. Naphthalene, a molecular solid with the formula C10H8
B. Silica, a network solid held together by covalent bonds with the formula SiO2
C. Calcium chloride, an ionic compound with the formula CaCl2
D. Water, an molecular compound with the formula H2O
The unknown solid with melting point of 78 degrees Celsius has been the molecular solid Naphthalene with formula [tex]\rm C_1_0H_8[/tex]. Thus, option A is correct.
Melting point has been defined as the temperature that has been able to transfer the solid to the liquid state.
The melting point has been higher for the substances with strong intermolecular interactions, and lower for weak attractive compounds.
Identity of the unknown sampleThe unknown sample has a melting point of 78 degree Celsius.
The molecular compounds have high melting point with strong intermolecular interactions, and ionic and covalent compounds have low melting point with weak intermolecular interactions.
The melting point of water has been zero degree Celsius.
Thus, the unknown solid with melting point of 78 degrees Celsius has been the molecular solid Naphthalene with formula [tex]\rm C_1_0H_8[/tex].
Thus, option A is correct.
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The most likely identity of the unknown white solid with a melting point of 78 °C is naphthalene, a molecular solid with the formula C10H8, commonly used in mothballs.
Explanation:If the unknown substance is a white solid at room temperature and has a melting point of 78 °C, the most likely candidate from the given options would be naphthalene, which is a molecular solid. This substance has the formula C10H8 and is well-known for its use in mothballs. It has a melting point close to the given temperature, whereas the other given substances have significantly higher melting points and different chemical and physical properties.
SiO2, or silica, is a covalent network solid and CaCl2, or calcium chloride, is an ionic compound. Both have melting points that are much higher than 78 °C. Meanwhile, H2O, water, is a molecular compound that is not a solid at room temperature, as it has a melting point of 0 °C. Therefore, option A, naphthalene, is the most likely identity of the unknown solid.
what are the properties of clay soils? check all that apply
1.is loose
2.retains water
3.drains quickly
4.are fine grained
5.have coarse particles
Answer: 2.retains water, 4. are fine grained
Explanation:
Clay is a kind of soil. It exhibit fine grained particles. It retains the organic matter and inorganic minerals. The ability to retain water is because of fine grained size aggregate of clay. As this kind of soil can retain moisture and exhibit minerals it is suitable for the growth of plants.
Identify the Lewis base in this balanced equation: Fe3+ H2O Fe(H2O)63+
Answer:H20
Explanation:
because it is the base that contributes electrons
Answer : The Lewis-base in this reaction is, water [tex]H_2O[/tex]
Explanation :
According to the Lewis acid-base theory,
Lewis acid : It is a substance that can accepts pairs of electrons to form a covalent bond.
Lewis-base : It is a substance that can donates pairs of electrons to form a covalent bond.
The given balanced equation is:
[tex]Fe^{3+}+6H_2O\rightarrow [Fe(H_2O)_6]^{3+}[/tex]
In this reaction, [tex]Fe^{3+}[/tex] ion is Lewis-acid and [tex]H_2O[/tex] is a Lewis-base. The [tex]H_2O[/tex] donates electrons to [tex]Fe^{3+}[/tex] ion to form [tex][Fe(H_2O)_6]^{3+}[/tex].
Hence, the Lewis-base in this reaction is, water [tex]H_2O[/tex]
write the complete equation for the neutralization reactions that take place when the following water solutions are mixed.
1.) KOH(aq) + HF(aq)
2.) HCl(aq) + LiOH(aq)
3.) H2SO4(aq) + NaOH(aq)
The molar mass of cadmium chloride is 183 g. what mass of CdCl2 would be present in 10.0 mL of 9 M solution?
The mass of CdCl₂ present in 10.0 mL of a 9 M solution is 16.47 grams.
Given:
Molar mass of CdCl₂ = 183 g/mol
Volume of solution = 10.0 mL = 0.010 L
Molarity of solution (concentration) = 9 M
The molarity (M) of a solution is defined as the number of moles of solute per liter of solution.
Molarity is commonly used to express the concentration of solutions in various chemical reactions and experiments.
To calculate the moles of CdCl₂:
Moles = Molarity x Volume
Moles = 9 M x 0.010 L
Moles = 0.09 mol
Now, to calculate the mass of CdCl₂:
Mass = Moles x Molar mass
Mass = 0.09 mol x 183 g/mol
Mass = 16.47 g
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What is scientific law how does a hypothesis become a law
Answer:
In general, a scientific law is the description of an observed phenomenon. It doesn't explain why the phenomenon exists or what causes it. The explanation of a phenomenon is called a scientific theory. It is a misconception that theories turn into laws with enough research.
Explanation:
Answer:
A scientific law is a description of an observed phenomenon.this is not an explanation of a phenomenon but a description.
Hypothesis becomes a law when they follow a line of reasoning and formulate a theory.then once a theory has been evaluated through a series of testing it becomes a law.
Hope this helps and if it does pls mark as brainliest answer
What are the coefficients that will balance this skeleton equation? N 2 + H 2 → NH 3
Final answer:
The coefficients that will balance the equation N₂ + H₂ → NH₃ are 1 for N₂, 3 for H₂, and 2 for NH₃.
Explanation:
Chemical equations express chemical reactions using symbols and formulas. Reactants on the left side transform into products on the right side. Balancing ensures conservation of mass. Coefficients in chemical equations represent the numerical ratios of reactants and products. They ensure the conservation of mass and atoms. Adjusting coefficients balances the equation, reflecting the correct stoichiometry of the reaction.
The coefficients that will balance the skeleton equation N₂ + H₂ → NH₃ are: 1 for N₂, 3 for H₂, and 2 for NH₃. The coefficients of a balanced equation represent the mole ratio required for the reaction to occur. In this case, one mole of N₂ reacts with three moles of H₂ to produce two moles of NH₃.
need asap
What is the role of the cell wall in plant cells?
Answer:
The cell wall in plant cells is responsible for cell protection, providing structural support, and giving shape to the cell.
Explanation:
The cell wall in plant cells is responsible for cell protection, providing structural support, and giving shape to the cell.
How does temperature affect the Keq of a reaction?
Answer:
D. Changing the temperature will change Keq.
Explanation:
The equilibrium constant expresses the relationship between the molar concentration of reactants and products. This constant is the Keq. It is temperature dependent and constant at a given temperature.
A change in temperature of an equilibrium system shifts the system to a new equilibrium point. A rise in temperature shifts the equilibrium position to the direction that absorbs heat and vice versa.
In summary, a shift in equilibrium which results from temperature change is actually a change in value of the equilibrium constant.
Answer: D. changing the temperature will change the K eq
Explanation:
Which formula equation represents the burning of sulfur to produce sulfur dioxide?
S(s) + O2(g) 4502(9)
2H2S(s) + 302(g) —> 2H20(0) + 2502(9)
4FeS2+1102 —> 2Fe2O3 + 8502
2802(g) + O2(9) V205 , 2503(9)
Answer:
S(s) + O2(g) → SO2(g)
The correct chemical equation that represents the burning of sulfur to form sulfur dioxide is S(s) + O2(g) -> SO2(g). This equation illustrates that one mole of sulfur reacts with one mole of oxygen to produce sulfur dioxide.
Explanation:The question is asking for the correct formula equation which represents the burning of sulfur to produce sulfur dioxide. The burning of sulfur in the presence of oxygen (O2) results in the formation of sulfur dioxide (SO2). This process can be represented by the following chemical equation:
S(s) + O2(g) —> SO2(g)
This shows that one mole of sulfur (S) reacts with one mole of Oxygen (O2) to produce one mole of sulfur dioxide (SO2).
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Which of the following is the best name for a compound made from calcium and bromine? (CaBr2) calcium bromide calcium dibromide monocalcium dibromide calcium bromine II
Answer:
Calcium Bromide
Explanation:
Metals like Calcium reacts with halogens like bromine to form Metal halides.
Metal + Halogen → Metal halide
The generally accepted names for compounds and elements are the IUPAC names,
Therefore for calcium and bromine, the IUPAC name of the salt formed is calcium bromide.
Answer:
Calcium bromide
Explanation:
Calcium bromide is mainly used as dense aqueous solutions for drilling fluids. It is also used in medicines, freeze mixtures and photography.
The nomenclature follows the general rule:
Anion Name + Cation Name
But this is only effective for those salts that are classified as simple salts, which means, salts that dissociate into water and form only one cation and one anion.
When we work with a salt called double, for example, this rule goes through some adjustments. It is one that presents in its constitution the presence of two cations accompanying an anion or two anions accompanying a cation. For this reason, when these salts undergo the dissociation phenomenon in water, they release two cations or two anions, depending on the salt with which they are working.
The double salt that has in its constitution two cations accompanying an anion is called double salt as the cation. To name such a salt, we must use the following naming rule:
Anion name + name of the two cations
The name of each cation is written according to the order of electropositivity. Thus, the most electropositive cation will be written first.
When H+ forms a bond with H2O to form he hulydronium ion H3O+, this bond is called a coordinate covalent bond because ?
Answer:
Because both the bonding electrons come from the oxygen atom.
Explanation:
A coordinate covalent bond is formed when both the bonding electrons are coming from the same atom.
Here in the given situation, when H+ forms a bond with the water molecule [tex] H _ 2 O [/tex] to form the hydronium ion [tex] H _ 3 O + [/tex], then it is referred to as a coordinate covalent bond since both the bonding electrons are coming from the oxygen atom.
Answer:
Both the shared electrons come from single atom
Explanation:
Coordinate covalent bond is a type of bond in which both the shared pair of electrons are come from single bond. Whereas in simple covalent bond, sharing electrons come from both the participant atoms.
Coordinate covalent bond is also called dative bond and the atom which share both the electrons are called donar atom.
For a coordinate covalent atom to from, one participant atom should have lone pair of electron and other atom should be deprived of electrons.
In [tex]H_2O[/tex] molecule, O atom has lone pair of electrons while H+ ions has deficiency of electrons, so O atom shares its lone pair of electrons with H+ ions which results in the formation of coordinate covalent bond and forms [tex]H_3O^+ molecules[/tex].
Absalon adds 1 g of salt to 1 L of room temperature water (25 °C). Then, he starts a timer and observes what happens. He notices that it takes 1 minute for the salt to dissolve. He decides to repeat his experiment, and he adds 1 g of salt to another 1 L of room temperature water (25 °C). After he adds the salt, he starts a timer. But, instead of watching the salt dissolve, he stirs the salt and water with a spoon until it dissolves. He notices that it only takes 30 seconds for the salt to dissolve in his second experiment.
Why does the salt dissolve faster in Absalon's second experiment?
Stirring the salt and water increases the polarity of the water molecules, which causes the ionic bonds of the salt to break.
Stirring the salt and water increases particle motion, which causes more collisions to occur between the water and salt.
Stirring the salt and water increases the surface area of the water, which causes more collisions to occur between the water and salt.
Stirring the salt and water increases the pressure on the solution, which causes the ionic bonds of the salt to break.
Answer:
B
Explanation:
I looked it up and found the answer lol
Answer: Option (b) is the correct answer.
Explanation:
When Absalon stirred the solution which is containing salt in water then there will occur disturbance into solution due to stirring.
As a result, particles will come in motion and hence, they tend to gain more kinetic energy. Due to which there will be more number of collisions between the solute (salt) and solvent (water) particles.
Hence, rate of reaction will increase and because of this salt will readily dissolve into water.
Thus, we can conclude that the salt dissolve faster in Absalon's second experiment because stirring the salt and water increases particle motion, which causes more collisions to occur between the water and salt.
We know we are originated from the combination of elements but where did the elements and compound came from. Where did the proton neutron electron or smallest particle came? Then Does god exists?Plz give me a good reason.
Which is the limiting reactant in the following chemical reaction: 4NH3+5O2=4NO+6H2O , if 4 grams of O2 is used and 2 grams of NH3 is used?
a H2O
b NH3
c NO
D O2
Answer:
D
Explanation:
O
2 is the limiting reagent because the least moles of this are used in the reaction.
Final answer:
Oxygen (O2) is the limiting reactant in the reaction 4NH3 + 5O2 = 4NO + 6H2O when 4 grams of O2 and 2 grams of NH3 are used, as it has a smaller ratio of moles to its coefficient in the balanced equation compared to NH3. So the correct option is D.
Explanation:
The limiting reactant in the chemical reaction 4NH3 + 5O2 = 4NO + 6H2O can be determined by calculating the moles of the reactants and comparing their mole ratio with the stoichiometry of the balanced equation. First, calculate the moles of NH3 and O2 using their molar masses (NH3: 17 g/mol, O2: 32 g/mol):
moles of NH3 = 2 g / 17 g/mol = 0.118 mol,moles of O2 = 4 g / 32 g/mol = 0.125 mol.Next, divide the moles of each reactant by their respective coefficients in the balanced equation:
ratio for NH3 = 0.118 mol / 4 = 0.0295,ratio for O2 = 0.125 mol / 5 = 0.025.Since the ratio for NH3 is larger than the ratio for O2, O2 is the limiting reactant. This means that not all of the NH3 will be used up in the reaction.
A sample of an unknown compound has a percent composition of 52.14% carbon, 13.13% hydrogen, and 34.73% oxygen. Which compounds could
the sample be?
CH3CH3CH202
C2H5OH
C4H10o2
C4h12o2 and ch3ch3ch2ooh
To determine which compounds an unknown sample could be, based on its percent composition, involves calculating the empirical formula from the given percentages and comparing it with the provided compound options.
Explanation:The question involves determining which compounds an unknown sample could be, based on its percent composition of 52.14% carbon, 13.13% hydrogen, and 34.73% oxygen. This requires an understanding of percent composition and the ability to calculate an empirical formula based on the given percentages. Given the complexity of the sample compositions and potential empirical formulas, it's essential to evaluate each option through stoichiometric calculations and compare their empirical formulas derived from the provided compositions to the actual compounds mentioned.
in the ideal gas law, was does n represent ?
Answer:
The letter n represents Moles
Explanation:
The Ideal Gas Law. The letter P represents Pressure, the letter V represents Volume, the letter n represents Moles, the letter R represents a constant (a certain number to make the equation work together), the letter T represents temperature.
Yes, In the ideal gas law, 'n' represents the number of moles of a gas. This quantity, along with pressure, volume, and temperature, forms part of the equation PV = nRT, which describes the state of an ideal gas.
The ideal gas law is an equation that describes the relationship between pressure, volume, temperature, and the number of moles of a gas and is generally written as PV = nRT. Here, P stands for pressure, V is volume, R is the ideal gas constant, and T is the temperature in Kelvin. Chemists use moles when working with this law to relate the amount of substances in a more manageable way, as opposed to counting the vast number of individual particles directly.
The law illustrates that, for an ideal gas, if the density (connected to the number of moles) or the temperature goes up, the pressure of the gas also tends to increase. However, this relationship is most accurate when gases do not have strong interactions between particles. In cases where gas particles do interact strongly, such as when gases are not in the ideal state, the ideal gas law may not accurately predict the behavior of the gas.
Compare similarities and differences between the Plum Pudding Model, Nuclear Model and Bohr Model (6 marks)
Answer:
The three models describes the structure of an atom based on different views.
Explanation:
Plum pudding model described the atom of consisting of negatively charged electrons embedded in positively charged substrates; this was later proven to be false. The Bohr's model described the electrons in an atom to orbit round the nucleus at different energy, the closer it's to the nucleus, the lesser the energy it needs. The Rutherford model claims the the nucleus of the atom contains protons and neutrons which forms the mass of the atom, the electrons surrounds the nucleus and it forms the volume of the atom.
The atom has been the smallest unit of matter. It has been revealed with the varies studies and models proposed to deliver the accepted and well illustrated model.
The Plum pudding model has been the first atomic model proposed by J.J. Thomson. The Rutherford model has been the well illustrated model of the atom.
Similarities and differences between the Atomic modelsThe Plum pudding model has been proposed by J.J. Thomson, the Nuclear model by Rutherford, and the Bohr model has been proposed by Bohr.
Similarities in atomic modelsThe atomic models have been proposed for the atom. All the models have been focused with a central positive nucleus, and negative electrons outside the nucleus.
Differences in atomic modelThe plum pudding model considered electrons to be distributed unequally outside the nucleus. The Nuclear model has been considered electrons to be present outside the nucleus in the orbital shells. The Bohr model has been able to explain the quantum address of the electron.
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Fission of uranium-235 products energy and ______
A. isotopes of smaller elements
B. isotopes of larger elements C. lighter isotopes of uranium D. heavier isotopes of uranium
Answer:
A
Explanation:
During fission, heavier unstable atoms are split into lighter and more stable atoms with the release of energy. Fission of Uranium-235 produces Barium and Krypton (which are lighter and more stable atoms) and neutrons. Barium has an atomic mass of 141 while that of Krypton is 92.
Answer:
a
Explanation:
Explain your reasoning for your formula prediction for Ba+2 and S-2. A neutral molecule requires equal numbers of cations and anions. Atoms will not combine unless their ions have an equal but opposite charge. The total charge of cations plus anions must equal zero. all of the above
Answer:
The total charge of cations plus anions must equal zero.
Explanation:
The result Barium sulfide which is arrived upon because the total charge of cation plus anions =0
+2+(-2)=0 as seen above. The product is an electrically neutral compound.
Ba²⁺+ S²⁻⇒BaS
The product is a solid which is in the looks of black ash.
Answer:
The answer is: The total charge of cations plus anions must equal zero.
Hope this helped :)
Explanation:
Mercury-203 undergoes beta minus decay. 203 80 Hg → 203 81 Tl + ? The subatomic particle produced is a(n) . 203 80 Hg → 203 81 Tl + 0 -1 e Is this the correct balanced equation? .
Answer:
A negative beta particle
Yes
Explanation:
The incomplete equation of the reaction:
²⁰³₈₀Hg → ²⁰³₈₁Tl + ?
In order to balance nuclear equations, we must conserve the mass number and atomic number.
For the mass number; 203 = 203 + a
a = 0
Atomic number; 80 = 81 + b
b = -1
The unknown has no mass number but an atomic number of -1
This a negative beta particle and it is designated as ⁰₋₁e
Answer:
1) Electron
2) Yes
Using the table on the right, complete each unit conversion by typing in the correct answer. 85.0 kg =_____ lb
Answer:
Using the table on the right, complete each unit conversion by typing in the correct answer.
85.0 kg =
187 lb
5.000 km =
3.125 mi
8.000 fl oz =
236.8 mL
14.600 oz =
414.64 g
Explanation:
Bolded ones are the answers for all of the questions!! You're welcomeee
Final answer:
To convert 85.0 kg to pounds, you multiply by the conversion factor of 2.205 lb/kg. The result should maintain the original number of significant figures, which in this case is three, so following the significant figures rule, the answer is rounded to 187 lb.
Explanation:
The student has asked for the conversion of 85.0 kilograms (kg) to pounds (lb). To perform the conversion, the appropriate conversion factor needs to be applied. Given that 1 kg is approximately equivalent to 2.205 lb, you would multiply the mass in kilograms by this conversion factor to find the equivalent weight in pounds. It's important to keep in mind the significant figures of the inexact number when calculating the final answer.
Here's the calculation:
85.0 kg x 2.205 lb/kg = 187.425 lb
However, since we are starting with 85.0 kg (which has three significant figures), our final answer should also have three significant figures. Therefore, we round 187.425 to 187 lb to match the significant figures.
Which of the following statements is true?
An atom consists of protons, electrons, and neutrons.
An atom consists of protons and neutrons.
An atom consists of electrons bonded to one another.
An atom consists of protons bonded to one another.
Answer:
The first option
Explanation:
Answer:
First Question, A, An atom consists of protons, electrons, and neutrons.
Second Question, B, A nucleus consists of protons and neutrons.
Explanation:
Match the formula for the following compound:
magnesium sulfate heptahydrate
MgS·7H2O
Mg2SO4·7H2O
Mg(SO4)2·7H2O
MgSO4·7H2O
valence of magnesium is 2
and valence of sulfate-ion is 2 too
answer: MgSO4•7H2O
Answer: [tex]MgSO_4.7H_2O[/tex]
Explanation:
[tex]MgSO_4[/tex] is an ionic compound because aluminium element is a metal and hydrogen element is a non-metal. The bond formed between a metal and a non-metal is always ionic in nature.
The nomenclature of ionic compounds is given by:
1. Positive is written first.
2. The negative ion is written next and a suffix is added at the end of the negative ion. The suffix written in case of [tex]SO_4^{2-}[/tex] is '-ate'.
Hence, the name of [tex]MgSO_4[/tex] is magnesium sulphate.
The water of crystallization is written as hydrate with the number of water molecules. As the name is heptahydrate, that means 7 water molecules are present.
Therefore, the correct answer is [tex]MgSO_4.7H_2O[/tex]