Answer:
One
Explanation:
In H2O, there's 2 hydrogen atoms and 1 oxygen atom
Answer:
Period
Explanation:
horizontal is a period and verticle is a group
Answer:
More energy will be released from the old substance than the new substance will need to form it's chemical bonds.
Explanation:
Given
Chemical A and Chemical B react in an exothermic reaction.
This means energy is released when they react to give products. The product formation also requires energy, which is got from the energy released when A and B reacts. The energy that is left after the formation of products is released as heat. So in order for a reaction to be exothermic, the energy released by the reactants should be more than the energy required for the new chemical bonds to be formed to give the products.
“Genes carry the information that determines your traits (say: trates), which are features or characteristics that are passed on to you — or inherited — from your parents. Each cell in the human body contains about 25,000 to 35,000 genes”.
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