The answer to this question would be: BaCl 2
Barium is an alkali metal with 56 atomic number. Barium located in the group 2 of the periodic table because it has 2 valence electrons. Chlorine is a nonmetal that has 1 valence electron. When react, it would need 2 chlorine for each barium as the valence electron of barium is twice the chlorine.
Answer:
It is either the third or fourth statement.
Explanation:
This is because exothermic reactions give off heat.
When reactants are mixed and heated and liquid collects in the sidearm of the apparatus, a chemical reaction is occurring.
<h3>What is a chemical reaction?</h3>
A chemical reaction is said to occur when reactants are combined to form products. We must note that the formation of products is evidenced by;
- Appearance of a liquid
- Appearance of a gas
- Appearance of a solid
Hence, when reactants are mixed and heated and liquid collects in the sidearm of the apparatus, a chemical reaction is occurring.
Learn more about chemical reaction:brainly.com/question/22817140
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