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Gwar [14]
3 years ago
8

A sample of pure calcium fluoride with a mass of 15.0 g contains 7.70 g of calcium. How much calcium is contained in 40.0 g of c

alcium fluoride?
Chemistry
1 answer:
Temka [501]3 years ago
6 0

Answer:

20.53 g.

Explanation:

  • Knowing that every 15.0 g of pure calcium fluoride contains 7.70 g of calcium.

<u>Using cross multiplication:</u>

15.0 g of pure calcium fluoride contains → 7.70 g of calcium.

40.0 g of pure calcium fluoride contains → ??? g of calcium.

<em>∴ The mass of Ca in 40.0 g of calcium fluoride</em> = (7.70 g)(40.0 g)/(15.0 g) = <em>20.53 g.</em>

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<h3>What is base dissociation constant? </h3>

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DISCLAIMER: The above question have mistake. The correct question is given as

Question:

Given that Ka for HBrO is 2. 8×10^−9 at 25°C. What is the value of Kb for BrO− at 25°C?

learn more about base dissociation constant:

brainly.com/question/9234362

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