Endothermic or exothermic? The reaction between ammonium nitrate and water absorbs heat from the surrounding environment.
Three drops of concentrated sulfuric acid added to 100 milliliters of water in a beaker makes the beaker hot.
Ammonium chloride dissolved in a beaker of water makes the beaker cold.
Uranium atoms are split to produce nuclear energy.
Water separates into hydrogen and oxygen when an electric current is run through it.
Methane and oxygen are combined to produce methanol and heat.

Endothermic

Exothermic

Endothermic

Exothermic

Exothermic

Exothermic

Explanation:

Endothermic is when a reaction absorbs heat.

Exothermic is when a reaction releases heat.

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6