All categories

3 years ago

How many molecules are there in 45.0 grams of CH4?

Chemistry

1 answer:

user100 [1]3 years ago

5 0

Answer: $16.93\times 10^{23}\ \text{molecules}$

Explanation:

Given

Mass of $CH_4$ $m=45\ gm$

Molar mass of $CH_4$ is $12+4\times1=16$

No of moles of $CH_4$ $=\dfrac{\text{Mass}}{\text{Molar mass}}=\frac{45}{16}$

No of Molecules in 45gm of $CH_4$ is

$\Rightarrow N_A\times\frac{45}{16}=6.022\times 10^{23}\times \frac{45}{16}\\\Rightarrow 16.93\times10^{23}\ \text{molecules}$

You might be interested in

A 45 mL sample of nitrogen gas is cooled from 135ºC to 15C in a container that can contract or expand at constant pressure. Wha

Vanyuwa [196]

Answer:

V₂ =31.8 mL

Explanation:

Given data:

Initial volume of gas = 45 mL

Initial temperature = 135°C (135+273 =408 K)

Final temperature = 15°C (15+273 =288 K)

Final volume of gas = ?

Solution:

The given problem will be solve through the Charles Law.

According to this law, The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure.

Mathematical expression:

V₁/T₁ = V₂/T₂

V₁ = Initial volume

T₁ = Initial temperature

V₂ = Final volume

T₂ = Final temperature

Now we will put the values in formula.

V₁/T₁ = V₂/T₂

V₂ = V₁T₂/T₁

V₂ = 45 mL × 288 K / 408 k

V₂ = 12960 mL.K / 408 K

V₂ =31.8 mL

8 0

3 years ago

Relative formula mass of glucose? (C6H12O6)

Rom4ik [11]

To find the mass of glucose, you must multiply the atomic weight of each of the elements in the molecule by the subscripts in the formula:

$C_{6}=6*(12.01g)=72.06g$

$H_{12}=12*(1.008g)=12.096g$

$O_{6}=6*(15.999g)=95.994g$

Then you add all of them together:

$72.06g+12.096g+95.994g=180.15g$

Therefore, the molar weight of glucose is 180.15 grams.

3 0

3 years ago

I really need help pls, will pay anything

Triss [41]

Explanation:

For the first part,

Reaction equation:

N₂ + 3H₂ → 2NH₃

Given:

Number of moles of NH₃ = 6 moles

Unknown:

Number of moles of N₂ = ?

Solution:

N₂ + 3H₂ → 2NH₃;

From the reaction above, we solve from the known specie to the unknown. Ensure that the equation is balanced;

2 moles of NH₃ is produced from 1 mole of N₂

6 moles of NH₃ will be produced from $\frac{6}{2}$ mole of N₂

= 3moles of N₂

The number of moles of N₂ is 3 moles

ii.

Given parameters:

Number of moles of sulfur = 2.4moles

Molar mass of sulfur = 32.07g/mol

Unknown:

Mass of sulfur = ?

Solution:

The number of moles of any substance can be found using the expression below;

Number of moles = $\frac{mass}{molar mass}$

Mass of sulfur = number of moles of sulfur x molar mass

Insert the parameters and solve;

Mass of sulfur = 2.4 x 32.07 = 76.97g

6 0

2 years ago

A slice of Swiss cheese contains 48 mg of sodium

Nookie1986 [14]

Answer: grams=0.048g, ounces=0.0017oz, 0.00011lb

Explanation:

Stoichiometry

48 mg x 1 g

÷ 1000 mg = 0.048 g

48 mg x 1 g x 16 oz

÷ 1000 mg ÷ 453.6 g = 0.0017 oz

48 mg x 1 g x 1 lb

÷ 1000 mg ÷ 453.6 g = 0.00011 lb

6 0

3 years ago

Iodine, I2, is a solid at room temperature but sublimes (converts from a solid into a gas) when warmed. What is the temperature

Stels [109]

<h3>Answer:</h3>

382.63 K

<h3>Explanation:</h3>

We are given;

Volume of Iodine as 71.4 mL
Mass of Iodine as 0.276 g
Pressure of Iodine as 0.478 atm

We are required to calculate the temperature of Iodine

We are going to use the ideal gas equation;

According to the ideal gas equation; PV = nRT, where R is the ideal gas constant, 0.082057 L.atm/mol.K.

Rearranging the formula;

T = PV ÷ nR

But, n, the number of moles = Mass ÷ Molar mass

Molar mass of iodine = 253.8089 g/mol

Thus, n = 0.276 g ÷ 253.8089 g/mol

= 0.001087 moles

Therefore;

T = (0.478 atm × 0.0714 L) ÷ (0.001087 moles × 0.082057)

= 382.63 K

Thus, the temperature of Iodine in Kelvin is 382.63 K

3 0

3 years ago