<span>Step 1: Ask a question or identify a problem. ...Step 2: Background research. ...Step 3: Form a hypothesis. ...Step 4: Experiment and observe. ...<span>Step 5: Draw a conclusion.</span></span>
Granite and pebbles are the answer
<u>Answer:</u>
Exothermic Reaction are those reaction, in which energy is released while in endothermic reaction are those, in which energy is absorbed.
<u>Explanation:</u>
First Reaction:
As in this reaction, energy is released
½H2(g) + ½I2(g) → HI(g), ΔH = +6.2 kcal/mole
so it is <em>exothermic reaction</em>
Second reaction:
As in this reaction, energy is absorbed
21.0 kcal/mole + C(s) + 2S(s) → CS2(l)
so it is <em>endothermic reactions</em>.
1. Dry Ice (solid carbon dioxide)
2. Iodine
3. Arsenic
4. Naphthalene