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DaniilM [7]
3 years ago
12

An atom has a mass number of 9 and 5 neutrons. What is its atomic number?

Chemistry
1 answer:
denis23 [38]3 years ago
7 0

Answer:

4

Explanation:

It should be 4

The mass is 9

There are 5    neutrons

There are 9 - 5 = 4 protons

So it is the 4th element on the periodic table.

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A sample of gas has a volume of 20.0 mL at STP. What will the volume be if the temperature is changed to 546 K and the pressure
Ostrovityanka [42]

The volume did not change, it remained at 20 ml

<h3>Further explanation</h3>

Given

20 ml a sample gas at STP(273 K, 1 atm)

T₂=546 K

P₂=2 atm

Required

The volume

Solution

Combined gas Law :

\tt \dfrac{P_1.V_1}{T_1}=\dfrac{P_2.V_2}{T_2}

Input the value :

\tt \dfrac{1\times 20}{273}=\dfrac{2\times V_2}{546}\\\\V_2=\dfrac{1\times 20\times 546}{273\times 2}\\\\V_2=20~ml

The volume does not change because the pressure and temperature are increased by the same ratio as the initial conditions (to 2x)

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ivanzaharov [21]
It is a. oxidation-reduction
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Calculate the formula mass of magnesium chloride, MgCl2?
viktelen [127]
Mg = 24.3
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