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Natasha2012 [34]
3 years ago
7

A strontium-90 atom that has a lost two electrons has __________ protons, __________ neutrons, and __________ electrons.

Chemistry
1 answer:
MAXImum [283]3 years ago
4 0
<span><em>Answer:</em>
A strontium-90 atom that has a lost two electrons has <u>38</u> protons, <u>52</u> neutrons, and <u>36</u> electrons.

<em>Explanation:
</em>Atomic number<em> of </em>Strontium (Sr) is 38. 
<em>Atomic number = number of protons 
</em>Hence, Strontium has 38 protons.

If the element is in neutral state,
                number of protons = number of electrons. 
Then, neutral Strontium atom should have 38 electrons. 
But the question says Sr has lost 2 electrons. Hence, number of electrons should be 38 - 2 = 36.

Mass number = number of protons + number of neutrons.

The given mass number is 90. Hence, number of neutrons should be 90 - 38 = 52.</span>
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