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r-ruslan [8.4K]
2 years ago
9

A student has a test tube that contains 50 mL of water. She wants to add a substance to the water that will cause the test tube

to become hot to the touch. Which of the following would be best for her to add to the water?
A.
a substance that releases heat when it reacts with water
B.
a substance that produces a gas when it reacts with water
C.
a substance that does not react with water
D.
a substance that absorbs heat when it reacts with water
Chemistry
1 answer:
PilotLPTM [1.2K]2 years ago
6 0
B
Hope it helps you
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Answer:

3.07 Cal/g

Explanation:

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We will use the following expression.

Q = C × ΔT

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According to the law of conservation of energy, the heat released by the candy has the same magnitude as the heat absorbed by the calorimeter.

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Help! I need help on how to do these problems.
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a. 3; b. 5; c. 10; d. 12

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For problems c. and d. we are given a strong base rather than acid. In this case, we can calculate the pOH:

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Strong bases similarly ionize to completion, producing [OH⁻] in the process; 1 x 10⁻⁴ M OH⁻ will be produced for c., and 1.0 x 10⁻² M OH⁻ produced for d. Taking the negative log of the hydroxide concentrations would yield a pOH of 4 for c. and a pOH of 2 for d.

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