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Juliette [100K]
3 years ago
10

Jim measures how long it takes for a toy car to roll down a ramp. He rolls the car down the ramp four times in the exact same wa

y.
Each roll, he measures the time it takes for the car to reach the bottom.
Jim's results will most likely show that
A. the time is about the same for each roll.
B.
the time is very different for each roll.
C. the time gets shorter for each roll.
D. the time gets longer for each roll.
Chemistry
1 answer:
Elina [12.6K]3 years ago
4 0
A- the time is about the same for each roll.
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This is an acid base reaction and the chemical equation for the above reaction is as follows;
KOH  + HClO₄ ---> KClO₄ + H₂O
the stoichiometry of acid to base is 1:1
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Number of KOH moles - 0.723 M/1000 mL/L x 25.0 mL = 0.018 mol
Number of HClO₄ moles - 0.273 M/1000 mL/L x 50 mL = 0.013 mol 
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pOH = -log(0.067 M)
pOH = 1.17
pOH + pH = 14
Therefore pH = 14 - 1.17 = 12.83
by knowing pH we can calculate the [H₃O⁺]
pH = -log [H₃O⁺]
[H₃O⁺] = antilog[-12.83]
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Which statement is correct about the rate of chemical reactions?
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The addition of a foreign body to a reaction may influence the speed of the reaction. If a foreign body increases the rate of reaction, it is a called a positive catalyst or simply a catalyst. A negative catalyst is called an inhibitor.

A catalyst is a substance that is introduced into a chemical reaction to change the rate of the reaction without itself being affected at the end of the reaction.

Catalysts helps to reduce reaction time of many slow reactions. Most catalysts are specific in their actions and works on certain reactions or substrates.

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