The amount of heat required is 9.0 kJ.
<em>q = mC</em>Δ<em>T
</em>
Δ<em>T</em> = <em>T</em>_f – <em>T</em>_i = 65 °C – 32 °C = 33 °C
<em>q</em> = 65 g × 4.184 J·°C⁻¹g⁻¹ × 33 °C = 9000 J = 9.0 kJ
Answer: The correct statements are:
- Objects “fall” toward the center of Earth.
- Objects accelerate at a rate of 9.8 m/s each second.
- Objects are pulled by Earth more strongly than they pull on Earth.
Explanation:
The gravity of the earth is the force which attracts the object to the center of the earth. When the any object with mass falls under the action of the gravity attains the acceleration of 9.8 
.
- Objects “fall” toward the center of Earth.
- Objects accelerate at a rate of 9.8 m/s each second.
- Objects are pulled by Earth more strongly than they pull on Earth.
Answer:
- Part a) 0.0104 moles copper(II) nitrate.
i) 0.0418 mole Cu
ii) 0.0209 mol Ag NO₃
Explanation:
<u>1) Balanced chemical reaction (single replacement):</u>
In a single replacement reaction a more acitve metal (Cu) replaces a less active metal (Ag)
- Cu + 2 Ag NO₃ → Cu (NO₃)₂ + 2 Ag
<u>2) Mole ratio: </u>
- 1 mole Cu : 2 mole Ag NO₃ : 2 mole Ag
<u />
<u>3) Moles of Ag</u>
- n = mass in grams / atomic mass
- atomic mass of Ag: 107.868 g/mol
- n = 2.25 g / 107.868 g/mol = 0.0209 mol Ag
<u>4) Moles of copper(II) nitrate:</u>
- Set the proportion using the mole ratio:
- 2 mole Ag / 1 mole Cu (NO₃)₂ = 0.0209 mole Ag / x
- Solve: x = 0.0209 / 2 mole Cu (NO₃)₂ = 0.0104 moles Cu(NO₃)₂
That is the answer of part a: 0.0104 moles copper(II) nitrate.
<u>5) Moles of each reactant</u>
i) Cu:
- Set a proportion using the theoretical mole ratio
1 mole Cu / 2 mole Ag = x / 0.0209 mol Ag
- Solve for x: x = 0.0209 / 2 mole Cu = 0.0418 mole Cu
ii) Ag NO₃
- Set a proportion using the teoretical mole ratio
2 mole Ag NO₃ / 2 mole Ag = x / 0.0209 mole Ag
- Solve for x: x = 0.0209 mol Ag NO₃
