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3 years ago

How many electrons does the predictable (most common) ion of calcium contain?

1 answer:

3 0

Answer: 18

Justification:

1) The most common ion of calcium is Ca 2+

2) That means that the atom, neutral calcium, has lost two electrons.

3) The atomic number of calcium is 20.

4) Atomic number is the number of protons, so calcium has 20 protons.

5) Therefore, the neutral atom of calcium also has 20 electrons (to make a net charge of zero).

6) Then, the ion Ca 2+ has 20 - 2 = 18 electrons.

Answer: 18 electrons.

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3 years ago

Hydrogen is unique among the elements because __________. 1. It has only one valence electron. 2. It is the only element that ca

Talja [164]

Answer:

3,4

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3 years ago

Which will cause an increase in the reaction rate between molecules?

Mariana [72]

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3 years ago

Which properties make a metal a good material to use for electrical wires? malleability and reactivity conductivity and ductilit

Schach [20]

The metal properties that make up electrical wires are conductivity and ductility. Conductivity is important for free electrons to flow, hence electricity. Ductility is as well integral for strips to be formed, but with ample strength that does not break the material.

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3 years ago

Read 2 more answers

Group the following electron configurations in pairs that would represent similar chemical properties at their atoms;

marishachu [46]

Answer: Pairs are: (a) and (d), (b) and (f), (c) and (e)

Explanation:

In a periodic table, elements are arranged in 18 vertical columns known as groups and 7 horizontal rows known as periods.

Elements arranged in a group show similar chemical properties because of the presence of same number of valence electrons.

Valence electrons are defined as the electrons which are present in the outermost shell of an atom. Outermost shell has the highest value of 'n' that is principal quantum number.

For the given options:

For a:

The given electronic configuration is: $1s^22s^22p^63s^2$

The number of valence electrons in the given configuration are 2

For b:

The given electronic configuration is: $1s^22s^22p^63s^3$

The number of valence electrons in the given configuration are [2 + 3] = 5

For c:

The given electronic configuration is: $1s^22s^22p^63s^23p^64s^23d^{10}4p^6$

The number of valence electrons in the given configuration are [2 + 6] = 8

For d:

The given electronic configuration is: $1s^22s^2$

The number of valence electrons in the given configuration are 2

For e:

The given electronic configuration is: $1s^22s^22p^6$

The number of valence electrons in the given configuration are [2 + 6] = 8

For f:

The given electronic configuration is: $1s^22s^22p^63s^23p^3$

The number of valence electrons in the given configuration are [2 + 3] = 5

Electronic configuration of (a) and (d) will form a pair, (b) and (f) will form a pair, (c) and (e) will form a pair and will have similar chemical properties.

Hence, the pairs are: (a) and (d), (b) and (f), (c) and (e)

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3 years ago