112ml. of oxygen at STP is subjected to liquefication. The mass of liquid oxygen obtained is

Options

A. 0.64 g
B. 0.16 g
C. 0.32 g
D. 0.96 g

Answer

To solve the problem of finding the mass of liquid oxygen obtained from 112 mL of oxygen at STP, we can follow these steps:

### Step 1: Understand the Volume of Gas at STP
At Standard Temperature and Pressure (STP), 1 mole of any ideal gas occupies 22.4 liters (or 22,400 mL).

### Step 2: Calculate the Number of Moles of Oxygen
We can calculate the number of moles of oxygen gas in 112 mL using the formula:

\[ \text{Number of moles} = \frac{\text{Volume of gas}}{\text{Molar volume at STP}} = \frac{112 \text{ mL}}{22400 \text{ mL/mol}} \]

Calculating this gives:

\[ \text{Number of moles} = \frac{112}{22400} = 0.005 \text{ moles} \]

### Step 3: Determine the Molar Mass of Oxygen
The molar mass of oxygen (O2) is approximately 32 g/mol.

### Step 4: Calculate the Mass of Liquid Oxygen
Now, we can find the mass of the liquid oxygen using the formula:

\[ \text{Mass} = \text{Number of moles} \times \text{Molar mass} \]

Substituting the values we have:

\[ \text{Mass} = 0.005 \text{ moles} \times 32 \text{ g/mol} = 0.16 \text{ grams} \]

### Final Answer
The mass of liquid oxygen obtained is **0.16 grams**.

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