All matter is made up of substances called elements, which have specific chemical and physical properties and cannot be broken down into other substances through ordinary chemical reactions. Gold, for instance, is an element, and so is carbon. There are 118 elements, but only 92 occur naturally.
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Answer:
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Explanation:
The expression can be solved mathematically as follows:
1)
Given
2)
Definition of sum
3)
/Associative property
4)
Distributive property
5)
Multiplication
6)
Subtraction.
7)
Multiplication/Associative property
8)
Associative property
9)
/Result
Answer:
potassium
The third alkali metal is K (potassium). The atomic number of K (potassium) is 19. Thus, the atomic number of third alkali metal is 19
Explanation: