The granite block transferred <u>4080 J</u> of energy, and the mass of the water is <u>35.8 g</u>.
1. <em>Energy from granite block
</em>
The formula for the heat (<em>q</em>) transferred is
<em>q = mC</em>Δ<em>T</em>
<em>m</em> = 126.1 g; <em>C</em> = 0.795 J·°C⁻¹g⁻¹; Δ<em>T</em> = <em>T</em>_f – <em>T</em>_i = 51.9 °C - 92.6 °C = -40.7 °C
∴ <em>q</em> = 126.1 g × 0.795 J·°C⁻¹g⁻¹ × (-40.7 °C) = -4080 J
The granite block transferred 4080 J.
2. <em>Mass of water
</em>
<em>q = mC</em>Δ<em>T
</em>
<em>m = q</em>/(<em>C</em>Δ<em>T</em>)
<em>q </em>= 4080 J; <em>C</em> = 4.186 J·°C⁻¹g⁻¹; Δ<em>T</em> = <em>T</em>_f – <em>T</em>_i = 51.9 °C – 24.7 °C = 27.2 °C
∴ <em>m</em> = 4080 J/(4.186 J·°C⁻¹g⁻¹ × 27.2 °C) = 35.8 g
The mass of the water is 35.8 g.
Answer: kinetic, move faster, potential, change form
Explanation:
Answer:
D. Brecci
The pattern of the rock below resembles the distinct pattern of brecci.
The pattern of conglomerate usually appears to be more round peices in the rock. The pattern of brecci has a more shard like appearance.
Hope this helps,
One of the virtuosos on Brainly
Answer:
pH = 3.3
Explanation:
Buffer solutions minimize changes in pH when quantities of acid or base are added into the mix. The typical buffer composition is a weak electrolyte (wk acid or weak base) plus the salt of the weak electrolyte. On addition of acid or base to the buffer solution, the solution chemistry functions to remove the acid or base by reacting with the components of the buffer to shift the equilibrium of the weak electrolyte left or right to remove the excess hydronium ions or hydroxide ions is a way that results in very little change in pH of the system. One should note that buffer solutions do not prevent changes in pH but minimize changes in pH. If enough acid or base is added the buffer chemistry can be destroyed.
In this problem, the weak electrolyte is HNO₂(aq) and the salt is KNO₂(aq). In equation, the buffer solution is 0.55M HNO₂ ⇄ H⁺ + 0.75M KNO₂⁻ . The potassium ion is a spectator ion and does not enter into determination of the pH of the solution. The object is to determine the hydronium ion concentration (H⁺) and apply to the expression pH = -log[H⁺].
Solution using the I.C.E. table:
HNO₂ ⇄ H⁺ + KNO₂⁻
C(i) 0.55M 0M 0.75M
ΔC -x +x +x
C(eq) 0.55M - x x 0.75M + x b/c [HNO₂] / Ka > 100, the x can be
dropped giving ...
≅0.55M x ≅0.75M
Ka = [H⁺][NO₂⁻]/[HNO₂] => [H⁺] = Ka · [HNO₂]/[NO₂⁻]
=> [H⁺] = 6.80x010⁻⁴(0.55) / (0.75) = 4.99 x 10⁻⁴M
pH = -log[H⁺] = -log(4.99 x 10⁻⁴) -(-3.3) = 3.3
Solution using the Henderson-Hasselbalch Equation:
pH = pKa + log[Base]/[Acid] = -log(Ka) + log[Base]/[Acid]
= -log(6.8 x 10⁻⁴) + log[(0.75M)/(0.55M)]
= -(-3.17) + 0.14 = 3.17 + 0.14 = 3.31 ≅ 3.3
