Answer is: <span>D. 327,992.8 J.
</span>m(granite) = 17 kg = 17000g.
ΔT(granite) = 21°C - 45°C = -24°C (-24K).<span>
cp(granite</span>)
= 0,804 J/g·°C, <span>specific heat capacity of
granite.
Q = m(granite</span>) · ΔT(granite) · cp(granite).<span>
Q = 17000 g ·(-24</span>°C)<span>· 0,804 J/g·K.
Q = -327990 J.
</span>The granite lost 327990 joules of energy.<span>
Q - </span>amount of energy gained or lost.<span>
</span>
Answer:
A. 0.143 M
B. 0.0523 M
Explanation:
A.
Let's consider the neutralization reaction between potassium hydroxide and potassium hydrogen phthalate (KHP).
KOH + KHC₈H₄O₄ → H₂O + K₂C₈H₄O₄
The molar mass of KHP is 204.22 g/mol. The moles corresponding to 1.08 g are:
1.08 g × (1 mol/204.22 g) = 5.28 × 10⁻³ mol
The molar ratio of KOH to KHC₈H₄O₄ is 1:1. The reacting moles of KOH are 5.28 × 10⁻³ moles.
5.28 × 10⁻³ moles of KOH occupy a volume of 36.8 mL. The molarity of the KOH solution is:
M = 5.28 × 10⁻³ mol / 0.0368 L = 0.143 M
B.
Let's consider the neutralization of potassium hydroxide and perchloric acid.
KOH + HClO₄ → KClO₄ + H₂O
When the molar ratio of acid (A) to base (B) is 1:1, we can use the following expression.

The population decreases when the birth rate is less than the death rate.