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Artyom0805 [142]
3 years ago
9

1. An atom of an elephant has atomic mass of 39 and has number of neutrons as 20 calculate protons number.

Chemistry
1 answer:
r-ruslan [8.4K]3 years ago
5 0

Answer:

See Explanation

Explanation:

1) Let us recall that;

Mass number = number of protons + number of neutrons

Where;

Number of protons = ?

Number of neutrons =20

Mass number =39

Number of protons = mass number - number of neutrons

Mass of protons =39 - 20= 19 protons

2) Atomic number = 13

Number of neutrons =14

Then the mass number =13 +14 =27

The symbol of the element is 27X13

The number of protons= the number of electrons =13

The atomic number is the same as the proton number =13

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The theoretical yield of urea : = 227.4 kg

<h3>Further explanation</h3>

Given

Reaction

2NH3(aq)+CO2(aq)→CH4N2O(aq)+H2O(l)

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211.4 kg of carbon dioxide

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Required

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Solution

mol Ammonia (MW=17 g/mol)

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3 0
3 years ago
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Elan Coil [88]

Answer:

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Alex17521 [72]

Answer:

the properties of three undiscovered elements  is the correct answer.

Explanation:

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The answer is "Liquid".

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MrRa [10]
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