Convert the following in kilogram.
(i) `0.91xx10^(-27)g` (Mass of electron)
(ii) `3.34xx10^(-24)g` (Mass of hydrogen molecule)

Answer

To convert the given masses from grams to kilograms, we can follow these steps:

### Step 1: Understand the Conversion Factor
1 kilogram (kg) is equal to 1000 grams (g). Therefore, to convert grams to kilograms, we can use the conversion factor:
\[ 1 \text{ g} = 10^{-3} \text{ kg} \]

### Step 2: Convert the Mass of the Electron
The mass of the electron is given as:
\[ 0.91 \times 10^{-27} \text{ g} \]

To convert this to kilograms:
\[ \text{Mass of electron in kg} = 0.91 \times 10^{-27} \text{ g} \times 10^{-3} \text{ kg/g} \]
\[ = 0.91 \times 10^{-30} \text{ kg} \]

### Step 3: Simplify the Expression
We can express \( 0.91 \times 10^{-30} \) in scientific notation:
\[ = 9.1 \times 10^{-31} \text{ kg} \]

### Step 4: Convert the Mass of the Hydrogen Molecule
The mass of the hydrogen molecule is given as:
\[ 3.34 \times 10^{-24} \text{ g} \]

To convert this to kilograms:
\[ \text{Mass of hydrogen molecule in kg} = 3.34 \times 10^{-24} \text{ g} \times 10^{-3} \text{ kg/g} \]
\[ = 3.34 \times 10^{-27} \text{ kg} \]

### Final Answers
1. The mass of the electron in kilograms is:
\[ 9.1 \times 10^{-31} \text{ kg} \]

2. The mass of the hydrogen molecule in kilograms is:
\[ 3.34 \times 10^{-27} \text{ kg} \]

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