Answer:
Quantitative experiments show that 4.18 Joules of heat energy are required to raise the temperature of 1g of water by 1°C. Thus, a liter (1000g) of water that increased from 24 to 25°C has absorbed 4.18 J/g°C x 1000g x 1°C or 4180 Joules of energy.
Answer is: concentration of hydrogenium ions is 9,54·10⁻⁵ M.
c(HNO₂) = 0,075 M.
c(NaNO₂) = 0,035 M.
Ka(HNO₂) = 4,5·10⁻⁵.
This is buffer solution, so use <span>Henderson–Hasselbalch equation:
pH = pKa + log(c(</span>NaNO₂) ÷ c(HNO₂)).
pH = -log(4,5·10⁻⁵) + log(0,035 M ÷ 0,075 M).
pH = 4,35 - 0,33.
pH = 4,02.
<span>[H</span>₃O⁺] = 10∧(-4,02).
<span>[H</span>₃O⁺] = 0,0000954 M = 9,54·10⁻⁵ M.
A chemical or physical change
Answer:
Approximately 
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Explanation:
Balanced equation for this reaction:
.
Look up the relative atomic mass of elements in the limiting reactant, 
, as well as those in the product of interest, 
:
Calculate the formula mass for both the limiting reactant and the product of interest:
.
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Calculate the quantity of the limiting reactant () available to this reaction:
.
Refer to the balanced equation for this reaction. The coefficients of the limiting reactant () and the product (
) are both 
. Thus:
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In other words, for every 
of formula units that are consumed, 
of formula units would (in theory) be produced. Thus, calculate the theoretical yield of 
in this experiment:
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Calculate the theoretical yield of this experiment in terms of the mass of expected to be produced:
.
Given that the actual yield in this question (in terms of the mass of ) is 
, calculate the percentage yield of this experiment:
.
This is false, because copper is an element.
To be solution, it has to have at least 2 different substances. Solid solution of metals is often called alloy.
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