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Ivahew [28]
3 years ago
10

An element has atomic number 10 and an atomic mass of 20. How many neutrons are in the atom of this element? A. 10 B. 20 C. 30 D

. 0 E. 200
Chemistry
1 answer:
MariettaO [177]3 years ago
3 0

Answer : The correct option is, (A) 10

Explanation :

Atomic number : It is defined as the number of protons or number of electrons.  That means,

Atomic number = number of protons = number of electrons

Atomic mass : It is defined as the sum of number of protons and number of neutrons.

Atomic mass = Number of neutrons + Number of protons

As we are given that,

The atomic number of an element = 10

The atomic mass of an element = 20

Now we have to determine the number of neutrons.

Atomic number = number of protons = 10

Atomic mass = Number of neutrons + Number of protons

Number of neutrons = Atomic mass - Number of protons

Number of neutrons = 20 - 10 = 10

Therefore, the number of neutrons are, 10

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3 0
3 years ago
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Explanation:

Given parameters:

Mass of water = 319.5g

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Final temperature = 100°C

Unknown:

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Solution:

The calories is the amount of heat added to the water. This can be determined using;

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learn more:

Specific heat brainly.com/question/3032746

#learnwithBrainly

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