Answer:
2.8 g KOH
Explanation:
We can find the amount of moles we need by multiplying 0.500 L and the molarity given, 0.10 M (molarity is moles of solute divided by liters of solution). The liters cancel out, leaving us with moles; we can then take the moles and convert it to grams of KOH by using the molar mass of KOH.
0.500 L x 0.10 mol/1 L x 56.106 g /1 mol = 2.8 g KOH (two significant figures)
3. The density of ethanol is 0.789 g/mL. How many grams of ethanol should be mixed with 225 mL of water to make a 4.5% (v/v) mixture?
Answer:
I don't know what to say sorry
How many particles are in a 34 g sample of Al2(SO4)3?
please help!
Answer:
5.98 × 10^22 particles
Explanation:
To get the number of particles (nA) in a substance, we multiply the number of moles of the substance by Avogadro's number (6.02 × 10^23)
The mass of Al2(SO4)3 given in this question is as follows: 34grams.
To convert this mass value to moles, we use;
Mole = mass/molar mass
Molar Mass of Al2(SO4)3 = 27(2) + {(32 + 16(4) }3
= 54 + (32 + 64)3
= 54 + 288
= 342g/mol
mole (n) = 34/342
n = 0.0994mol
number of particles (nA) of Al2(SO4)3 = 0.0994 × 6.02 × 10^23
= 0.598 × 10^23
= 5.98 × 10^22 particles
Which of the following is a TRUE statement?
a.
A molecule always has three types of elements present
b.
Compounds always include the elements hydrogen and sodium
c.
Compounds include things we use in our everyday lives
d.
All elements prefer to hang out with other elements and form molecules
Answer:
b
Explanation:
Number 6
Metals react with _______ to form co.pounds that are like alkaline.
A. Non metals
B. Oxygen
C. Hydrogen
D. Metalloids
Answer:
B) Oxygen atoms
Explanation:
When metals react oxygen atom then they tend to form metal oxides which are basic in nature. This is because when metal oxides are added in water then it results in the formation of metal hydroxides which are alkaline in nature
How many molecules of carbon dioxide, CO2, are in 38.5 moles?
Answer:
2.31847E25
Explanation:
One mole of anything contains 6.022 x 10^23 items.
which pollutants come from air? How and why do these form?
Answer:
Air pollution is caused by solid and liquid particles and certain gases that are suspended in the air. These particles and gases can come from car and truck exhaust, factories, dust, pollen, mold spores, volcanoes and wildfires.
Explanation:
An atom of a certain element has 19 protons, 19 electrons, and a mass number of 39. This element is very reactive. How many neutrons are in this atom?
Answer:
There would be [tex]20[/tex] neutrons in that atom.
Explanation:
The mass number of an atom is the sum of:
the number of neutrons in this atom, andthe number of protons in this atom.Electrons do not contribute to the mass number of an atom.
From the question:
Mass number of this atom: [tex]39[/tex].Number of protons in this atom: [tex]19[/tex].[tex](\text{Mass Number}) = (\text{Number of protons}) + (\text{Number of neutrons})[/tex].
In this atom:
[tex]39 = 19 + (\text{Number of neutrons})[/tex].
Hence, the number of neutrons would be [tex]39 - 19 = 20[/tex].
help me pretty please
Answer:
If i had to take a stab at it would say C
Explanation:
Answer:
I think it might be C but not 100% sure.
Explanation:
When the object transmits all color frequencies.
A container at equilibrium contains the following concentrations: [Hz] - 0.30 M and [HI]
0.90 M. The equilibrium constant is equal to 6.0. What is the concentration of I2 at
equilibrium?
Hzig) + 1218 = 2 Hle)
Answer: The concentration of [tex]I_2[/tex] at equilibrium is 0.45 M
Explanation:
Equilibrium constant is defined as the ratio of concentration of products to the concentration of reactants each raised to the power their stoichiometric ratios. It is expressed as [tex]K_c[/tex]
For the given chemical reaction:
[tex]H_2(g)+I_2(g)\rightarrow 2HI(g)[/tex]
The expression for [tex]K_c[/tex] is written as:
[tex]K_c=\frac{[HI]^2}{[H_2]^1[I_2]^1}[/tex]
[tex]6.0=\frac{(0.90)^2}{(0.30)^1\times (I_2)^1}[/tex]
[tex][I_2]=0.45M[/tex]
Thus concentration of [tex]I_2[/tex] at equilibrium is 0.45 M
Pick one answer do not put any links please
What do we examine to understand the differences between the different states of matter?
A. Electronegativity of the matter present
B. Moles of matter present.
C. Behavior of the particles
D. Size of the particles
Answer:
C. Behavior of the particles
chelp meeee this is science btw but eahhhh
Answer: KCIO3
Explanation:
The graph shows that it is the lowest at 0 degrees meaning that it has the lowest solubility
Answer:
KOL c
Explanation:
An organism whose cell contains a nucleus.
Answer:
Eukaryotes
Explanation:
Calculate the density of carbon dioxide at STP
Answer:
Density = mass/volume
= 44/22.4
= 1.96 gram/liter
The density of the Carbon Dioxide at S.T.P. (Standard Temperature and Volume) is 1.96 gram/liter.
You had a closed tank of air at a pressure of 4 atm and temperature of 20 degrees Celsius. When the tank and the air are heated to 40 degrees Celsius, what is the pressure if the volume remains constant?
Answer:
The pressure will be 4.27 atm.
Explanation:
Gay-Lussac's law can be expressed mathematically as follows:
[tex]\frac{P}{T} =k[/tex]
Where P = pressure, T = temperature, K = Constant
This law indicates that the quotient between pressure and temperature is constant.
This law indicates that, as long as the volume of the container containing the gas is constant, as the temperature increases, the gas molecules move faster. Then the number of collisions with the walls increases, that is, the pressure increases. That is, the pressure of the gas is directly proportional to its temperature.
In short, when there is a constant volume, as the temperature increases, the pressure of the gas increases. And when the temperature is decreased, the pressure of the gas decreases.
You want to study two different states, an initial state and a final state. You have a gas that is at a pressure P1 and a temperature T1 at the beginning of the experiment. By varying the temperature to a new value T2, then the pressure will change to P2, and the following will be fulfilled:
[tex]\frac{P1}{T1} =\frac{P2}{T2}[/tex]
In this case:
P1= 4 atmT1= 20 C= 293 K (being 0 C= 273 K)P2= ?T2= 40 C= 313 KReplacing:
[tex]\frac{4 atm}{293 K} =\frac{P2}{313 K}[/tex]
Solving:
[tex]P2= 313 K* \frac{4 atm}{293 K}[/tex]
P2= 4.27 atm
The pressure will be 4.27 atm.
The pH of tomato juice is 4, thus tomato is a (an) _______________ substance
Answer:
Acidic
Explanation:
pH from 0-6.9 are acidic substances
pH of 7 are neutral
pH above 7 to 14 are badic substances
Answer: Acidic
Explanation:
PH of 1-6 is considered acidic.
PH of 7 is neutral.
PH of 8-14 is considered basic (alkaline)
Windmills are sometimes helpful for some small rural communities.
True
False
Answer:
true
Explanation:
Earthquakes and what kind of plate boundary movement cause them?
what are the five major types of celestial bodies in the solar system
Answer:
the Sun, planets, satellites, comets, asteroids and meteoroids.
Explanation:
hope it helps :)
how acceptance of responsibility influence affective in communication
Answer:
f
Explanation:
Which of the following phases of matter has a fixed volume but not a fixed shape?
A Liquid B Gas C Solid D Plasma
Answer:
C. solidExplanation:
Solid is a hard and not able to flow; not like a liquid or gas. Having no holes; not hollow. Something that is not liquid and gas. Solid has fixed volume but not a fixed shape.
The liquid is something that flows freely; a substance that is not solid or gas.
Gas is a substance that neither liquid nor solid, e.g. air.
Plasma is an electrically neutral ionized gas in an electric discharge; distinctly different from solids and liquids and normal gases.
Therefore, the correct answer is C. solid.
Answer:
A. Liquid
Explanation:
the guy above me is wrong
As altitude increases, what happens to air pressure the choices are it fluctuates, it increases, it decreases or it stays the same
Answer:
it decreases
Explanation:
It is a common saying the pressure decreases with height. This means that as altitude increases, the pressure of air decreases. The higher you go above sea level, the pressure becomes lesser.
This is as a result of decrease in the amount of air above sea level and hence a decrease in the density of air as altitude increases.
Hence, with increasing altitude, pressure decreases.
Answer:
It decreases
Explanation:
as pstnonsonjoku says in their answer.
I cannot give you anything more than I just did a question on this an it was correct because i'm in a timed test and just happend to see this!
Have a great nightish day!
How many grams of Si are there in a sample of Si that contains the same number of moles as a 60.8 gram sample of P?
Answer:
55.1 g Si.
Explanation:
Hello there!
In this case, for the given mole-mole relationship, it is possible to set up the following mole ratio as the moles of Si and P are the same:
1 mol Si = 1 mol P.
Next, since one mole of silicon has a mass of 28.09 g and one of phosphorous of 31.0 g, we can set up the following expression for the mass of silicon:
[tex]60.8gP*\frac{1molP}{31.0gP}*\frac{1molSi}{1molP}*\frac{28.09gSi}{1molSi}[/tex]
Therefore, the result is 55.1 grams of silicon.
Best regards!
When performing a neutralization reaction, how should students test the solution to be sure which is the acid and which is the base?
Explanation:
La reacción entre un ácido y una base se llama neutralización. Cuando en la reacción participan un ácido fuerte y una base fuerte se obtiene una sal y agua. Si una de las especies es de naturaleza débil y la neutralización se produce en disolución acuosa también se obtiene su respectiva especie conjugada y agua.
6) A student measures out 96.21 g of sulfur for an experiment. How many moles of Sulfur are in this
sample? (show your work!)
Atomic mass of Sulfur = 32g
32g of Sulfur is one mole.
1g of Sulfur is [tex] \frac{1}{32} moles [/tex]
96.21g of Sulfur is [tex] \frac{96.21}{32} moles=> 3moles(appx) [/tex]
Answer:
[tex]\boxed {\boxed {\sf 3 \ moles \ sulfur}}[/tex]
Explanation:
To convert from grams to moles, the molar mass is used. This value is the number of grams in 1 mole of a substance and it can be found on the Periodic Table. Look for Sulfur or S.
Sulfur: 32.07 g/molWe use this as a ratio.
[tex]\frac {32.07 \ g \ S}{1 \ mo;\l\ S }[/tex]
Multiply by the given number of grams.
[tex]96.21 \ g \ S*\frac {32.07 \ g \ S}{1 \ mo\l\ S }[/tex]
Flip the fraction so the grams of sulfur cancel out.
[tex]96.21 \ g \ S*\frac {1 \ mol \ S}{32.07 \ g \ S }[/tex]
[tex]96.21*\frac {1 \ mol \ S}{32.07 }[/tex]
[tex]\frac {96.21 \ mol \ S}{32.07 }= 3 \ mol \ S[/tex]
96.21 grams of sulfur is equal to 3 moles of sulfur.
PLEASE HELP ME
What answer is it?
Over millions of years silt washed into a lake formed layers of sedimentary rock. What type of rock was likely formed?
Answer:
Explanation:
siltstone
Over millions of years, silt washed into a lake formed layers of sedimentary rock. What type of rock was likely formed? A type of detrital sedimentary rock called siltstone was the likely product of this process.
pleaaseeee help im failing so bad3
Do you think it is a good idea for all scientists to use the same periodic table of elements? Why or why not?
Can yall help me with this one, thanks!
Answer:
Element atom molar mass Total % composition
Na 1 23 40 57.5 %
O 1 16 40 40%
H 1 1 40 2.5 %
The given compound is NaOH.
Na : number of atom= 1
Molar mass= 23 g/mol
Total mass of NaOH = 40 g/mol
% composition by mass = [tex]\frac{\text {mass of atom}}{\text {Total mass}}\times 100=\frac{23}{40}\times 100=57.5\%[/tex]
O : number of atom= 1
Molar mass= 16 g/mol
Total mass of NaOH = 40 g/mol
% composition by mass = [tex]\frac{\text {mass of atom}}{\text {Total mass}}\times 100=\frac{16}{40}\times 100=40\%[/tex]
H : number of atom= 1
Molar mass= 1 g/mol
Total mass of NaOH = 40 g/mol
% composition by mass = [tex]\frac{\text {mass of atom}}{\text {Total mass}}\times 100=\frac{1}{40}\times 100=2.5\%[/tex]