All categories

3 years ago

How many molecules are present in a sample of carbon dioxide, CO2 with a mass of 168.2?

Chemistry

1 answer:

Hoochie [10]3 years ago

6 0

Answer:

Explanation:

Always remember that 1 mole is just a way of saying 6.02 x 10^23 molecules. Because this is a huge number it is easier to use moles. It corresponds nicely ecause 12 grams of carbon is one mole (note the Mr of carbon is 12) and 44g of CO2 is one mole of CO2 (note that CO2 has Mr 44). You need to use the equation n = m/Mr . In words this is: number of moles = the mass (in grams) divided by the Molar Mass. You can think of this as the number of moles is equal to the mass of the amount you have divided by the mass of one mole (the molar mass). To find the molar mass of CO2 you need to use the periodic table. 12 + 16 + 16 = 44 So you need to do: 168.2 divided by 44 which will give you number of moles.

You might be interested in

The bomb calorimeter in Exercise 102 is filled with 987g water. The initial temperature of the calorimeter contents is 23.32. A

Sholpan [36]

Answer:

25.907°C

Explanation:

In Exercise 102, heat capacity of bomb calorimeter is 6.660 kJ/°C

The heat of combustion of benzoic acid is equivalent to the total heat energy released to the bomb calorimeter and water in the calorimeter.

Thus:

$-q_{combust} = q_{water} + q_{calori}$

$q_{combust}$ = heat of combustion of benzoic acid

$q_{water}$ = heat energy released to water

$q_{calori}$ = heat energy released to the calorimeter

Therefore,

$-m_{combust}*H_{combust} = [m_{water}*c_{water} + C_{calori}]*(T_{f} - T_{i})$

1.056*26.42 = [0.987*4.18 + 6.66]( $T_{f}$ - 23.32)

27.8995 = [4.12566+6.660]( $T_{f}$ - 23.32)

( $T_{f}$ - 23.32) = 27.8995/10.7857 = 2.587

$T_{f}$ = 23.32 + 2.587 = 25.907°C

4 0

3 years ago

How many grams of ammonium chloride (gram formula mass= 53.5 g) are contained in .500 L of a 2.00 M solution?

Elza [17]

Answer:

53.5g of NH4Cl

Explanation:

First, we need to obtain the number of mole of NH4Cl. This is illustrated below:

Volume = 0.5L

Molarity = 2M

Mole =?

Molarity = mole /Volume

Mole = Molarity x Volume

Mole = 2 x 0.5

Mole = 1mole

Now, let us convert 1mole of NH4Cl to gram. This is illustrated below:

Molar Mass of NH4Cl = 53.5g/mol

Number of mole = 1

Mass =?

Number of mole = Mass /Molar Mass

Mass = number of mole x molar Mass

Mass = 1 x 53.5

Mass = 53.5g

Therefore, 53.5g of NH4Cl is contained in the solution.

8 0

3 years ago

If a jar of honey sits for a long time, sugar may crystallize in the jar. Describe two possible causes for the crystallization.

n200080 [17]

Dryness and temperature are the primary reasons but also the type of honey.

3 0

3 years ago

what is the effect of using higher concentration of sodium hydrogen carbonate on the rate of reaction?

Alex

Increasing the concentration of one or more reactants will often increase the rate of reaction. This occurs because a higher concentration of a reactant will lead to more collisions of that reactant in a specific time period.

Reaction rate increases with concentration, as described by the rate law and explained by collision theory. As reactant concentration increases, the frequency of collision increases. The rate of gaseous reactions increases with pressure, which is, in fact, equivalent to an increase in concentration of the gas.

7 0

2 years ago

Which of the following indicates that a chemical change has happened during cooking?

Vera_Pavlovna [14]

The food darkens because the color is changing in the food.

6 0

3 years ago