1 mol of ideal gas at STP occupies 22.4 (or 22.7 depending on the convention being used for STP) liters in volume. I will use 22.4 so 17.88*22.4 = 400.5 L

4 0

3 years ago

How many moles of sand (SiO2) are in 30 g of sand?

anastassius [24]

<h3>Answer:</h3>

0.50 mol SiO₂

<h3>General Formulas and Concepts:</h3>

<u>Math</u>

<u>Pre-Algebra</u>

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right

<u>Chemistry</u>

<u>Atomic Structure</u>

Reading a Periodic Table
Using Dimensional Analysis

<h3>Explanation:</h3>

<u>Step 1: Define</u>

30 g SiO₂ (sand)

<u>Step 2: Identify Conversions</u>

Molar Mass of Si - 28.09 g/mol

Molar Mass of O - 16.00 g/mol

Molar Mass of SiO₂ - 28.09 + 2(16.00) = 60.09 g/mol

<u>Step 3: Convert</u>

Set up: $\displaystyle 30 \ g \ SiO_2(\frac{1 \ mol \ SiO_2}{60.09 \ g \ SiO_2})$
Multiply/Divide: $\displaystyle 0.499251 \ mol \ SiO_2$

<u>Step 4: Check</u>

<em>Follow sig figs and round. We are given 2 sig figs.</em>

0.499251 mol SiO₂ ≈ 0.50 mol SiO₂

5 0

3 years ago

Read 2 more answers

How many hydrogen atoms are in 89.5 g of<br> C6H6 ?<br> Answer in units of atoms.

Elodia [21]

Solution :

Molar mass of $C_6H_6$ is :

M = 6×12 + 6×1 g

M = 78 g

78 gram of $C_6H_6$ contains $6.022 \times 10^{23}$ molecules.

So, 89.5 gram of $C_6H_6$ contains :

$n = 6.022 \times 10^{23} \times \dfrac{89.5}{78}\\\\n = 6.91 \times 10^{23}$

Now, from the formula we can see that one molecule of $C_6H_6$ contains 2 hydrogen atom . So, number of hydrogen atom are :

$h = 2\times 6.91 \times 10^{23}\\\\h = 1.38 \times 10^{22}\ atoms$

Hence, this is the required solution.

8 0

2 years ago