Answer:
The first equation
Explanation:
For these problems, it is best to label and record how many of each element are on each side of the equation. The first equation has 1 Ca, 2H, and 2Cl on both sides while the second equation has 3H on the left and 2H on the right making the second equation incorrect.
Answer:

Explanation:
1. First take the cylinder volume formula:

2. Then take the values for the radius and the height of the cylinder and replace them into the formula:

3. Solve the equation:



Answer:
The reaction is exothermic (option 4)
Explanation:
P4 + 5O2 → P4O10 + 712 kcal
In chemical reactions heat can be absorbed or released:
⇒in the first case, when heat is absorbed, this is called an endothermic reaction. The products have more energy than the reactants. The reaction requires or absorbs energy from it's surroundings. That means that in this reaction energy , in the form of heat, will be absorbed by the reactants.
⇒ when heat is released, this is called an exothermic reaction. The reactants have more energy than the products. The reaction gives or releases energy to it's surroundings. That means that in this reaction energy , in the form of heat, will be released by the reactants.
in the case of P4 + 5O2 → P4O10 + 712 kcal
We notice that on the right side, which is the product side, there is a positive amount of energy. This means that the energy is released by the the reactants, in this reaction. <u>The reaction is exothermic.</u>
.
Answer:
Explanation:
final temperature of the cube
initial temperature of the cube
mass of the cube
specific heat of aluminum