chalk contains 3% of carbon 10% of calcium and 12% of oxigen find the amount in grams of each of these substances in 1 kg of chalk

Answer

To find the amount of each substance in grams in 1 kg of chalk, we can follow these steps:

### Step 1: Understand the total weight of chalk
1 kg of chalk is equal to 1000 grams.

### Step 2: Calculate the amount of Carbon
- The percentage of Carbon in chalk is 3%.
- To find the amount of Carbon in grams, use the formula:
\[ \text{Amount of Carbon} = \left(\frac{\text{Percentage of Carbon}}{100}\right) \times \text{Total weight of chalk} \]
- Plugging in the values:
\[ \text{Amount of Carbon} = \left(\frac{3}{100}\right) \times 1000 = 30 \text{ grams} \]

### Step 3: Calculate the amount of Calcium
- The percentage of Calcium in chalk is 10%.
- Using the same formula:
\[ \text{Amount of Calcium} = \left(\frac{\text{Percentage of Calcium}}{100}\right) \times \text{Total weight of chalk} \]
- Plugging in the values:
\[ \text{Amount of Calcium} = \left(\frac{10}{100}\right) \times 1000 = 100 \text{ grams} \]

### Step 4: Calculate the amount of Oxygen
- The percentage of Oxygen in chalk is 12%.
- Again, using the same formula:
\[ \text{Amount of Oxygen} = \left(\frac{\text{Percentage of Oxygen}}{100}\right) \times \text{Total weight of chalk} \]
- Plugging in the values:
\[ \text{Amount of Oxygen} = \left(\frac{12}{100}\right) \times 1000 = 120 \text{ grams} \]

### Final Results
- Amount of Carbon: 30 grams
- Amount of Calcium: 100 grams
- Amount of Oxygen: 120 grams