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2 years ago

Pls some one help 1 mark question

Chemistry

1 answer:

Tatiana [17]2 years ago

7 0

Answer:

See below

Explanation:

Helium belongs to group VIII of the periodic table "Noble gases". It has only 1 electronic shell and that too contains 2 electrons according to the accommodation of the shell. Hence, it's electronic shell is complete. This is the reason, Helium is chemically unreactive.

$\rule[225]{225}{2}$

Hope this helped!

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Whats the answer to 7/2 × 1/5?

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Answer:

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Explanation:

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3 years ago

For the reaction: N2O5(g) \longrightarrow&longrightarrow; 2NO2(g) + 1/2O2(g)

ivanzaharov [21]

The given equation from the problem above is already balance,
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3 years ago

15.0 mL of an unknown clear liquid is added to a 50 mL graduated cylinder. The mass of the liquid is determined to be 12.7 grams

sveticcg [70]

Answer:

$\boxed {\tt A. \ d=0.85 \ g/mL}$

Explanation:

Density is found by dividing the mass by the volume.

$d=\frac{m}{v}$

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Substitute the values into the formula.

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Divide.

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3 years ago

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saw5 [17]

Answer:

Total cost = $40.25 (Approx)

Explanation:

Given:

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Total weight of candy = 0.98 kg

1 ounce = 0.028 kg (approx).

Total weight of candy = 0.98 kg / 0.028

Total weight of candy = 35 ounce (Approx)

Total cost = 35 × $1.15

Total cost = $40.25 (Approx)

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3 years ago