Answer : The final temperature of the copper is, 
Solution :
Formula used :
where,
Q = heat gained = 299 cal
m = mass of copper = 52 g
c = specific heat of copper = 
= final temperature = ?
= initial temperature = 
Now put all the given values in the above formula, we get the final temperature of copper.
Therefore, the final temperature of the copper is,
Answer: (3) Energy is absorbed as bonds are broken, and energy is released as bonds are formed.
Explanation:
1) The equation given is H₂(g) + Cl₂(g) → 2HCl(g) + energy
2) The energy is shown in the product side, so energy is a product of the reaction, so energy is release.
But this is just the net energy of the process. You need more insight to deal with the energy changes in the reaction.
3) Chemical bonds store energy; this stored energy is the potential chemical energy of the molecules.
When a chemical reaction occurs, the first stage is to brake bonds.
Braking chemical bonds requires energy to overcome the bond energy. Braking bonds always absorbs energy.
On the other hand, forming bonds always release energy.
The neat energy of the reaction is the difference between the energy needed to break bonds and the energy released when new bonds form.
So, regardless the fact that, in the chemical equation that represents the reaction a net energy release is shown, you know that energy is absorbed as bonds are broken, and energy is released as bonds are formed (option 3).
Given Data:
P₁ = 122 atm
P₂ = 112 atm
V₁ = 113 L
V₂ = ?
Solution:
Let suppose the gas is acting ideally. According to Ideal gas equation, keeping the temperature constant,
P₁ V₁ = P₂ V₂
Solving for V₂,
V₂ = P₁ V₁ / P₂
Putting Values,
V₂ = (122 atm × 113 L) ÷ 112 atm
V₂ = 113 L
Converting Volume to Moles,
As,
22.4 L is occupied by = 1 mole of He gas
So,
113 L will occupy = X moles of He gas
Solving for X,
X = (113 L × 1 mole) ÷ 22.4 L
X = 5.04 Moles of He
Answer:
28.57 grams are in (NO3)2
Explanation:
