Answer:
Below.
Explanation:
True:
A piece of gold is made only of gold atoms.
Untrue:
Protons have negative charges ( they are positive).
All molecules are compounds . (Oxygen gas O2 is a molecule but not a compound as the 2 atoms are the same).
Compounds have the same properties as the elements they are made from.
20 N force moving a box to 30 meters distance. How much work id done? if it takes 10 sec to do this work, how much power is used.
Answer:
Work done = 600 J
Power used = 60 W
Explanation:
Given:
Force acting on the box is, [tex]F=20\ N[/tex]
Displacement of the box is, [tex]S=30\ m[/tex]
Time taken for the work, [tex]t=10\ s[/tex]
Now, we know that, work is said to be done by a force only when there is displacement caused by the force in its direction.
Here, the force acting on the box causes a displacement of 30 m in its direction. So, work done is equal to the product of force and displacement caused.
Therefore, work done on the box is given as:
[tex]Work=Force\times Displacement\\Work=F\times S\\Work=(20\ N)\times (30\ m)\\Work=600\ J[/tex]
Therefore, the work done is 600 J.
Now, we know that, power is given as work done per unit time.
So, power used is given as:
[tex]Power=\frac{Work}{Time}\\\\Power=\frac{600\ J}{10\ s}\\\\Power=60\ W[/tex]
Therefore, the power used is 60 W.
Different ____________of an element have different numbers of neutrons.
Answer:
Isotopes
Explanation:
Answer: Isotopes
Explanation: Every atom/element is defined by the number of protons. So if it has 1 proton it's hydrogen no matter what, if it has 2 protons it's helium no matter what and so on. So if you know the number of protons, you know the element.
You can change the neutrons and you will get isotopes. Atoms that have different numbers of neutrons are called isotopes of each other. However, the element is the same but one is going to be a little bit heavier or lighter than another.
238 93 Np → 0 -1 e+ ?
Answer:
²³⁸₉₃Np → Pu₉₄²³⁸ + ⁰₋₁e
Explanation:
²³⁸₉₃Np → Pu₉₄²³⁸ + ⁰₋₁e
Beta radiations:
Beta radiations are result from the beta decay in which electron is ejected. The neutron inside of the nucleus converted into the proton an thus emit the electron which is called β particle.
The mass of beta particle is smaller than the alpha particles.
They can travel in air in few meter distance.
These radiations can penetrate into the human skin.
The sheet of aluminium is used to block the beta radiation
⁴₆C → ¹⁴₇N + ⁰₋₁e
The beta radiations are emitted in this reaction. The one electron is ejected and neutron is converted into proton.
Since the questions were asked so late, the only reason why I am answering this question is for the people who have the same question.
So, this question is asked like this:
Complete the following radioactive decay problem.
238 Np ⟶ 0 e + ___ ___
93 -1 ___
The answer is:
238 Pu
94
238 Np ⟶ 0 e + 238 Pu
93 -1 94
dot structure for magnesium
The dot structure for magnesium illustrates it losing its two outermost electrons when forming compounds like MgO, indicating its tendency to achieve stability. Magnesium can participate in more complex bonding geometries, such as 4-coordinate (tetrahedral), but in the simple formation of magnesium oxide, the focus is on the ionic bond and electron transfer.
Explanation:The question asks for the dot structure for magnesium, focusing specifically on its bonding and coordination number in chemical compounds. Magnesium, with an atomic number of 12, has its electrons arranged in a [Ne]3s² configuration. This means magnesium has two electrons in its outermost shell that it tends to lose to achieve a stable electronic arrangement, resembling the nearest noble gas, neon. When forming ionic compounds like magnesium oxide (MgO), magnesium donates its two outermost electrons to oxygen, resulting in a structure where magnesium has no dots around its symbol, indicating it has lost its valence electrons.
Magnesium's tendency to form compounds with specific geometries, either 4-coordinate (tetrahedral) or 6-coordinate (octahedral), highlights its versatility in chemical bonding. However, in the simpler case of forming ionic bonds, as in MgO, the focus is primarily on the transfer of electrons rather than the arrangement in complex geometries. The transformation into MgO exemplifies this process, underscoring the ionic character of the bond formed between magnesium and oxygen, a key concept in understanding magnesium's chemical behavior.
When 17.28 mL of a 0.078 M aqueous solution of Na2SO4 is combined with 11.30 mL of a 0.20 M aqueous solution of NaCl and 7.84 mL of a 0.26 M aqueous solution of KCl, what is the total concentration of Na+ in the combined solution?
Answer:
[ Na+ ]sln = 0.136 M
Explanation:
Na2SO4 → 2Na+(aq) + SO42-(aq)NaCl → Na+(aq) + Cl-(aq)KCl → K+(aq) + Cl-(aq)∴ mol Na2SO4 = ( 0.01728 L)×(0.078 mol/L) = 1.348 E-3 mol Na2SO4
⇒ mol Na+ = (1.348 E-3 mol Na2SO4)×(2 mol Na+/mol Na2SO4)
⇒ mol Na+ = 2.696 E-3 mol
∴ mol NaCl = (0.01130 L)×(0.20 mol/L) = 2.26 E-3 mol NaCl
⇒ mol Na+ = (2.26 E-3 mol NaCl)×(mol Na+/mol NaCl) = 2.26 E-3 mol Na+
⇒ total moles Na+ = 2.696 E-3 mol + 2.26 E-3 mol = 4.956 E-3 mol Na+
∴ total V sln = 17.28 mL + 11.30 mL + 7.84 mL = 36.42 mL = 0.03642 L sln
⇒ [ Na+ ]sln = (4.956 E-3 mol)/(0.03642 L) = 0.136 M
a force of 20N acts upon a 5kg block. calculate the acceleration of the object.
Answer:
4 m/s²
Explanation:
F/m
20N/4kg=
a= 4 m/s²
7 Be + 2 HCl →BeCl2+ H2
My theoretical yield of beryllium chloride was 12.7 grams. If my actual
yield was 5.4 grams, what was my percent yield?
Answer:
The percent yield is 42.52%.
Explanation:
Theoretical yield of beryllium chloride = 12.7 g
Actual yield of the beryllium chloride = 5.4 g
The formula used for the percent yield will be :
[tex]\text{Percent yield}=\frac{\text{Actual yield}}{\text{Theoretical yield}}\times 100[/tex]
Now put all the given values in this formula, we get:
[tex]\%(yield)=\frac{5.4 g}{12.7 g}\times 100=42.52\%[/tex]
The percent yield is 42.52%.
most regulatory signs are __
Most regulatory signs are used to control the movement of traffic and they help the people to follow the rules and they are in the shape of vertical triangle
Explanation:
These sign are one that help to regulate the traffic for the traffic direction like the lane use, parking, turning, speed and in other special situation these signs are called as regulatory signs
They are most often in the shape of triangle with a red circle or a red dot in it indicating the signs and the direction in which they must move and the rule that they must not follow
Some of the examples are no right turn, no left turn and no U-turn
Which biome has multistory communities?
O A. Taiga
O B. Tropical rain forest
O C. Temperate grassland
D. Desert
Answer:
The correct option is B) Tropical rain forest
Explanation:
The tropical rain forest biome acquires four main characteristics:
1: Increased amounts of rainfall in a year
2: high average temperatures
3: soil that is not enriched with nutrients
4: increased level of biodiversity.
Extreme levels of biodiversity can be seen in the tropical rain forest biome. Hence, due to increased biodiversity, this biome has multistory communities. This biome contains about 50% of the world's known animal and plant species.
Answer: B :)
Explanation:
Energy stored in the bonds that hold together the atoms and molecules of all substances is called Energy stored in the bonds that hold together the atoms and molecules of all substances is called
Answer:
Chemical energy!
Answer:
CHEMICAL ENERGY is your correct answer for this question
Explanation:
Consider the reaction Au(OH)3 + Hl — Au + 12 + H2O.
Label the half-reactions as oxidation (use "O") or reduction (use "R").
21 +2 +2e
Aut3 + 3e → Au
Answer:
1)O
2)R
Explanation:
Edge
The given one is a redox reaction. The oxidation reaction is the change from HI to I₂ and the reduction reaction is the metallic reduction of gold from the + 3 state to zero state.
What is redox reaction ?A redox reaction is a combination of both oxidation and reduction. Oxidation is the process of reacting with oxygen or loss of electrons. Whereas, reduction is the gain of one or more electrons.
In an oxidation reaction, the electron will be after the arrow and in reduction reaction the electron is gaining and it will be before the arrow in the chemical equation.
For the given reaction,
oxidation -
[tex]\rm Au^{3+} + 3e^{-} \rightarrow Au[/tex]
The reduction half reaction is written as:
[tex]\rm 2I^{-} \rightarrow I_{2} + 2e^{-}[/tex]
Find more on redox reaction :
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Complete the following radioactive decay problem.
14 7 N+ 1 0 n – ?C+}н
Answer:
¹⁴₆C → ¹⁴₇N + ⁰₋₁e
Explanation:
Beta radiations:
Beta radiations are result from the beta decay in which electron is ejected. The neutron inside of the nucleus converted into the proton an thus emit the electron which is called β particle.
The mass of beta particle is smaller than the alpha particles.
They can travel in air in few meter distance.
These radiations can penetrate into the human skin.
The sheet of aluminium is used to block the beta radiation
⁴₆C → ¹⁴₇N + ⁰₋₁e
The beta radiations are emitted in this reaction. The one electron is ejected and neutron is converted into proton.
Answer: 14N7 + 1n0 = 14C6 + 1H1
Explanation: The question shows how atoms are being represented by the number of proton and the number of electron.
By simply taking mass balance for the left and right hand sides, that is:
14N+1n =?C+ 1H
?C = 15-1 =14
Also,
N7+n0 = C? + H1
C? = 7+0-1
C? =6
Hence,
?C? = 14C6
How are atomic emission spectra used to identify elements? A) As the atom emits photons at precise frequencies it creates a similar atomic emission spectra to other atoms within its group. B) Atoms absorb photons and emit energy at definitive frequencies creating a universal atomic emission spectra common to all atoms. C) When the atom absorbs photons, energy can only be emitted at specific frequencies creating a characteristic atomic emission spectra. D) The atom absorbs photons and emits a continuous spectrum of energy but only certain frequencies can be detected creating the spectra.
Answer:
c
Explanation:
Answer:
The correct answer is option C) When the atom absorbs photons, energy can only be emitted at specific frequencies creating a characteristic atomic emission spectra.
Explanation:
Emission spectrometry is a spectroscopic technique that analyzes the wavelengths of photons emitted by atoms or molecules during their transition from an excited state to a lower energy state. Each element emits a characteristic set of discrete wavelengths based on its electronic structure.
That is, each atom is capable of emitting or absorbing electromagnetic radiation, although only at some frequencies that are characteristic of each of the different chemical elements. If a certain element is stimulated in its gas phase, its atoms emit radiation at certain frequencies of the visible, which constitute its emission spectrum.
Expressed in other words, when a substance radiates with electromagnetic radiation the electrons choose the radiation of this continuous spectrum to produce jumps at higher levels (excited state).
When an electron jumps from its fundamental state to higher energy levels (excited state) and falls back to lower energy levels, the emission of a photon of a defined wavelength occurs that appears as a specific line or line in the spectrum broadcast. Electromagnetic radiation from radiation after passing through the substance is missing a series of lines that correspond to electronic jumps from the fundamental state to the excited state. It is what is called an absorption spectrum.
In summary, because each atom is capable of emitting or absorbing electromagnetic radiation, although only at some frequencies that are characteristic of each of the different chemical elements, the correct answer is option C) When the atom absorbs photons, energy can only be emitted at specific frequencies creating a characteristic atomic emission spectra.
explain the law of conservative of energy, give a specific example using kinetic and potential energy that shows how energy is conversed.
Answer:
The Law of Conservation of Energy states that energy cannot be created or destroyed. In other words, the total energy of a system remains constant. This is an important concept to remember when dealing with energy problems. The two basic forms of energy that we will focus on are kinetic energy and potential energy.
Explanation:
In physics and chemistry, the law of conservation of energy states that the total energy of an isolated system remains constant; it is said to be conserved over time. This law means that energy can neither be created nor destroyed; rather, it can only be transformed or transferred from one form to another.
Im bad at these questions hope it helps and have a good day.
An engineer chooses to use bamboo as a building material because it grows
quickly and needs little space to grow. This is an example of Apex
Answer:
This is an example of Green design.
Explanation:
Green design can be described as a method in which any building project is made by minimizing the harmful effects of construction on humans and environment. Green design is a sustainable design which is better for the economy too. In a green design, eco- friendly materials are used for construction works.
In the scenario discussed in the question, an engineer is using bamboo as a building material due to its eco- friendly features. Hence, it is an example of green design.
- How are elements that are gases at room temperature designated in the periodic table?
Answer:
They are found in various parts of the periodic table: the whole group of the noble gases (8A), as well as some elements of alkali metals (1A), groups 5A, 6A and 7A (halogens)
Explanation:
There are a total of 11 elements in the periodic table which are gases at room temperature and standard atmospheric pressure.
Considering the periodic table, there's first of all one prominent group, the noble gases, group 8A. The whole group contains gases, those are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe) and radon (Rn).
The remaining ones are also typically diatomic at room temperature. First of all, hydrogen (H) in group 1A. At room temperature, it exists as a diatomic gas, [tex]H_2[/tex].
We also have one diatomic gas in group 5A, this is nitrogen, [tex]N_2[/tex]. Another diatomic gas is found in group 6A, this is oxygen, [tex]O_2[/tex].
The final gases belong to the group of halogens, group 7A, those are also diatomic, fluorine ([tex]F_2[/tex]) and chlorine ([tex]Cl_2[/tex]).
Thomas had a volume of 8.5 g of sodium chloride. What is the molar mass.?
Answer:
58.44 g/mol
Explanation:
In this problem, make sure to remember that volume is measured in mL, L or any other units of volume. Remember that g represents grams, and grams is a measure of mass.
However, independent of what mass or what volume we take, molar mass is known to be an intensive property. That is, molar mass doesn't depend on any external conditions or any measurements.
Molar mass solely depends on the chemical structure of a compound and is a constant number at any given conditions.
In this problem, we are given sodium chloride, NaCl. In order to find its molar mass, we need to refer to the periodic table, find the atomic masses of Na and Cl and then add them up to have the molar mass of NaCl:
[tex]M_{NaCl} = M_{Na} + M_{Cl} = 22.99 g/mol + 35.453 g/mol = 58.44 g/mol[/tex]
Can anyone help with any of these questions :)
Answer: 1.D
2. A
3. D
Explanation:
Classify the following as homogeneous and heterogeneous mixtures.
a) Soda water b)Milk c) Air d) Soil e) Blood
Answer:
Homogeneous mixture
a) Soda Water
b)Milk
c) Air
Heterogeneous mixture
d) Soil
e) Blood
c) Air
Explanation:
Mixture:
mixture is made up of different atoms and can be separated into its component by physical mean.
• The properties of the mixture are not same and contains the properties of all those component present in it.
• mixture is a combination of one or more Pure substances and can be separated by simple physical methods.
• it have varying boiling and melting point.
There are two types of mixture
Homogeneous mixture and heterogeneous mixture
Homogeneous mixture:
It have same uniform appearance and the different components cannot be distinguished by naked eye.
Heterogeneous mixture:
It do not have uniform appearance and the different components of the mixture can be distinguished and observed by naked eye.
Classification of the given mixtures
Homogeneous mixture Heterogeneous mixture
a) Soda Water d) Soil
b)Milk e) Blood
c) Air
Cho recorded the weather in her town for a week. She wrote down her observations in the table below. Mon Tue Wed Thu Fri Sat Sun High Temperature (degrees C) 23 22 22 21 17 14 14 Amount of Precipitation (cm) 0 0 0 0 1 3 5 If the trend in the weather pattern continues over the next week, what kind of weather do you predict Cho's town will have next week?
Answer:
If this trend continues, the following week will be cooler, and a large amount of rain will fall.
Explanation:
Patterns and trends can often be found in data sets. During the week that Cho recorded the weather, the temperatures consistently dropped by one to four degrees each day. At the end of the week, the amount of precipitation increased daily.
Answer:
it will be cold and rain
Explanation:
did it on study island
HELP!!!!!!!!!!!!!...!.!.!!..!.!
Answer : The correct option is, (C) 2-octene
Explanation :
Structural formula or bond-line formula : In the structural formula, the bonding and type of bonds which holds the atoms in molecule together are shown.
In bond-line formula, the lines are used between the bonded atoms and the atoms are also shown.
The basic rules for naming of organic compounds are :
First select the longest possible carbon chain.
For the number of carbon atom, we add prefix as 'meth' for 1, 'eth' for 2, 'prop' for 3, 'but' for 4, 'pent' for 5, 'hex' for 6, 'sept' for 7, 'oct' for 8, 'nona' for 9 and 'deca' for 10.
A suffix '-ane' is added at the end of the name of alkane.
If two of more similar alkyl groups are present, then the words 'di', 'tri' 'tetra' and so on are used to specify the number of times these alkyl groups appear in the chain.
In the given hydrocarbon, the longest possible carbon chain number is 8 that means we add prefix 'oct' and suffix '-ene' for double bond. So, the name of given molecule will be, 2-octene.
Hence, the name of the given molecule is, 2-octene.
atomic weight of Na is 23
atomic weight of Cl is 35
what is the percentage of sodium in NaCl?
Answer:
[tex]\large \boxed{40\, \%}[/tex]
Explanation:
1. Calculate the molar mass of NaCl
Na = 23 g
Cl = 35 g
Tot. = 58 g
2. Calculate the mass percent of Na
[tex]\text{\% of element} = \dfrac{\text{mass of element}}{\text{mass of compound}} \times 100 \, \% = \dfrac{\text{23 g}}{\text{58 g}} \times 100 \, \% =\mathbf{40\, \%}}[/tex]
[tex]\text{The percentage of Na in NaCl is $\large \boxed{\mathbf{40\, \% }}$}[/tex]
Ex1. how many moles correspond to 250 g of each of the following compounds?
a. NaCl
b. KNO,
c. H, 0,
d. KHSO,
Ex2. Calculate how many particles are contained in:
a. 1.5 g of potassium, K
b. 0.470 g of oxygen, 0,
c. 0.555 g of silver chloride,
AgCl
Ex3. Determines how many molecules of ethyl alcohol, C, H, OH (d - 0.79 g / mL), are in a bottle that contains 200 mL of it.
Answer:
Ex1 = 4.3 moles
Explanation:
for Ex 1
** Number of mole = Mass (g) / Molecular weight ' Mw' (g/mole)
for a = NaCl , first you must be calculate Mw = look to periodic table
Atomic weight for Na is 22.9 = 23 g and for Cl is 35.45 = 35 g
so Mw for NaCl = 23+35 = 58 g/mole
so Number of Moles for NaCl 250 g is
Number of Moles = 250 / 58 = 4.3 moles
do same for others ...
good luck ..
Answer:
Ex1. a) n NaCl = 4.277 mol NaCl
b) n KNO2 = 2.938 mol KNO2
c) n H2O2 = 7.349 mol H2O2
d) n KHSO3 = 2.080 mol KHSO3
Ex2. a) 2.31 E22 particles contained in 1.5 g K
b) 1.77 E22 particles contained in 0.470 g O
c) 2.332 E21 particles contained in 0.555 g AgCl
Ex3. molecules C2H5OH = 2.065 E24 molecules contained in 200 mL
Explanation:
Ex1. n = mass (m) / molecular weight (Mw)
a) Mw NaCl = 22.989 + 35.453 = 58.442 g/mol
⇒ n NaCl = (250 g NaCl)/(58.442 g/mol) = 4.277 mol NaCl
b) Mw KNO2 = 39.0983 + 14.0067 + (2)15.9994 = 85.104 g/mol
⇒ n KNO2 = (250 g KNO2)/(85.104 g/mol) = 2.938 mol KNO2
c) Mw H2O2 = (2)(1.00794) + (2)15.9994 = 34.015 g/mol
⇒ n H2O2 = (250 g H2O)/(34.015 g/mol) = 7.349 mol H2O
d) Mw KHSO3 = 39.0983 + 1.00794 + 32.065 + 15.9994(3) = 120.169 g/mol
⇒ n KHSO3 = (250 g KHSO3)/(120.169 g/mol) = 2.080 mol KHSO3
Ex2. n = (m) / (Mw)
∴ 1 mol ≡ 6.022 E 23 particles
a) Mw K = 39.0983 g/mol
⇒ K = (1.5 g K)×(mol/39.0983 g K)×(6.022 E23 part/mol) = 2.31 E22 particles
b) Mw O = 15.9994 g/mol
⇒ O = (0.470 g O)×(mol/15.9994 g O)×(6.022 E23 part/mol) = 1.77 E22 part
c) Mw AgCl = 107.8682 + 35.453 = 143.32 g/mol AgCl
⇒ AgCl = (0.555 g)×(mol/143.32 g)×(6.022 E23 part/mol) = 2.332 E21 part.
Ex3. ethyl alcohol ( C2H5OH)
∴ δ C2H5OH = 0.79 g/mL
∴ V = 200 mL
⇒ molecules C2H5OH = ?
1 mol ≡ 6.022 E23 molecules∴ Mw C2H5OH = (2)12.0107 + (5)1.00794 + 15.9994 + 1.00794 = 46.068 g/mol
⇒ molecules C2H5OH = (200 mL)×(0.79 g/mL)×(mol/46.068 g)×(6.022 E23 molecules/mol)
⇒ molecules C2H5OH = 2.065 E24 molecules C2H5OH
explain the relationship between plate tectonics and volcanos
Answer:
Plates sliding past each other cause friction and heat. Subducting plates melt into the mantle, and diverging plates create new crust material. Subducting plates, where one tectonic plate is being driven under another, are associated with volcanoes and earthquakes.
Explanation:
What does isotope mean
｡☆✼★ ━━━━━━━━━━━━━━ ☾
It's an atom with the same number of protons but a different number of neutrons and thus, a different mass number.
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Explanation: Every atom/element is defined by its protons so if it has 1 atom it's hydrogen no matter what, if it has 2 protons it's helium no matter what and so on. If you know the number or protons, you know the element.
You can change the number of neutrons in the nucleus and you'll get isotopes. So atoms that have different numbers of neutrons are isotopes of each other. However, the element is the same but one is going to be a little bit heavier or lighter than another.
So, isotopes are different versions of an element.
someone please help me pass my chem class!!!
5.000 moles of an ideal gas occupies 10.00 liters at a temperature of -3.000 degrees Celsius.
What is the pressure on the gas?
a) 22 atmospheres (atm)
b) 11,220 kilopascals (kPa)
c) 11.08 atmospheres
d) 1108 atmospheres
Answer:
B
Explanation:
Using the ideal gas law equation PV = nRT, and by converting the temperature to Kelvin, the pressure of the ideal gas is calculated to be 11.08 atmospheres.
The question pertains to the calculation of the pressure of an ideal gas given a certain amount of moles, volume, and temperature. To find the pressure on the gas, we use the ideal gas law equation PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature in kelvins.
First, we convert the temperature from Celsius to Kelvin: T(K) = -3.000 "+ 273.15 = 270.15 K.
We then use the value for R when pressure is in atmospheres, which is 0.0821 L imes atm/(K imes mol). With the given volume of 10.00 liters and the amount of 5.000 moles, the calculation is as follows:
P = (nRT)/V
P = (5.000 mol imes 0.0821 L imes atm/(K imes mol) imes 270.15 K) / 10.00 L
P = 11.08 atm
Thus, the pressure on the gas is 11.08 atmospheres, which corresponds to option (c).
limitation of modern periodic table
Answer:
The periodic table is a table representing all the elements found in nature.
Following are the limitations of the modern periodic table:
Hydrogen does not have a fixed position in this table. It matches the properties of group 1 and group 17.There are no separate positions for different isotopes of an element in the periodic table. The lanthanides and actinides series are not present in the main body of this table.How many grams are KBr are needed to make a saturated solution in 100g of water at 30c
Explanation:
To calculate that you need to know the value of the Kps (constant of solubility) at 30°C of KBr in water.
When the product of the concentrations of both ions (Br- and K+) equals the Kps, the solution is saturated.
Given the disociation of the salt in water:
[tex]KBr \longrightarrow K^+ + Br^-[/tex]
The concentration of both ions are equal (1:1 ratio) and the same as the concentration of KBr added.
The Kps:
[tex]Kps=[K^+][Br^-][/tex]
[tex][KBr]=(Kps)^{1/2}[/tex]
[KBr] are moles of the salt per litre of water
Assuming a density of water of 1 g/cm3, 100 g are 0.1 litre
To calculate the mass:
[tex]m=[KBr]*M*0.1 litre[/tex]
where M is the molecular weight of the salt.
[tex]65 \text{ grams of KBr}[/tex] is needed to make a saturated solution in 100g of water at 30C
To determine the amount of potassium bromide (KBr) needed to make a saturated solution in 100 grams of water at 30°C, one must refer to the solubility curve or table for KBr. The solubility curve provides the maximum amount of solute (in this case, KBr) that can be dissolved in a given amount of solvent (water) at a specific temperature.
At 30°C, the solubility of KBr in water is approximately 65 grams per 100 grams of water. This means that 65 grams of KBr can be dissolved in 100 grams of water to create a saturated solution at this temperature.
Therefore, the answer is: [tex]\[\boxed{65 \text{ grams of KBr}}\][/tex]
To make a saturated solution of KBr in 100 grams of water at 30°C, one would need to dissolve 65 grams of KBr in 100 grams of water. If more than 65 grams of KBr were added, the excess would not dissolve, and the solution would still be saturated. If less than 65 grams were used, the solution would not be saturated unless the solubility decreases due to some other factor, such as the presence of a common ion or a change in temperature.
The answer is: [tex]65 \text{ grams of KBr}.[/tex]
Which stage of the cell involves cell growth and DNA replication?
Answer: Interphase
Explanation: This is the stage in mitosis where the cell grows, and DNA is being replicated. This happens during the Synthesis Phase of Interphase.
Answer: C interphase
Explanation:
In an acid-base titration, 23.30 mL of hydrochloric acid were neutralized by 19.50 mL of 0.315 mol/L potassium hydroxide. Calculate the concentration of the hydrochloric acid.
Answer: 0.264mol/L
Explanation:Please see attachment for explanation