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Nesterboy [21]
4 years ago
13

What is true about the element calcium(Ca, atomic number 20)? Choose all that apply.

Chemistry
2 answers:
Marat540 [252]4 years ago
7 0
It has 2 valence electrons

THANK ME
Shkiper50 [21]4 years ago
5 0

Answer:

It has 2 valence electrons

It is a metal.

Explanation:

Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal.

In chemistry, a metal is an element that readily forms positive ions (cations) by losing electrons.

Calcium belongs to group 2 and would give up it's two valence electrons in reactions.

The electronic configuration is given as;

Ca : 1s2 2s2 2p6 3s2 3p6 4s2 or [Ar] 4s²

Valence electron represents the outermost electrons.

The correct options are;

It has 2 valence electrons

It is a metal.

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How does a balanced chemical equation illustrate that mass is never lost or gained in a chemical reaction?​
monitta

Answer:

Explanation:

Because if the equation is truly balanced, the elements on one side equal the element numbers on the other. Take a simple example.

Ba(OH)2 + 2HCl ==> BaCl2 + 2HOH

Now consider what is true.

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Ba                             1                                              1

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H                               4                                            4

Cl                              2                                             2

Nothing has changed going from the left to the right. You may wonder how you get 4 for the hydrogens.

Ba(OH)2  has 2 hydrogens. You multiply the 2 by the hydrogens in the brackets.

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Answer:

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