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3 years ago

In the ground state, an atom of which element has two valence electrons?

2 answers:

6 0

I am unsure if your teacher has taught you this, but, on a periodic table (of which you can find photos of on google) the numbers above each group how many valence electrons the atom has :) at 10 it restarts at 1

Akimi4 [234]3 years ago

5 0

I would say Ni so yeah thats ur answer

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What is 33 divided by 1862

beks73 [17]

0.01772288- Calculators do come in handy for this haha

4 0

3 years ago

Read 2 more answers

A glass blower can bend and shape a piece of glass that has been heated. Is glass a crystalline or an amorphous solid?

zavuch27 [327]

it would be a crystalline solid, because it could be extended in multiple directions.

5 0

3 years ago

A sample of sodium sulfite has a mass of 2.80 g.

Gnom [1K]

Answer:

For a: The number of sodium ions in given amount of sodium sulfite are $2.65\times 10^{22}$

For b: The number of sulfite ions in given amount of sodium sulfite are $1.325\times 10^{22}$

For c: The mass of one formula unit of sodium ions is $2.09\times 10^{-22}$ grams

Explanation:

The chemical formula of sodium sulfite is $Na_2SO_3$ . It is formed by the combination of 2 sodium $(Na^+)$ ions and 1 sulfite $(SO_3^{2-})$ ions

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Given mass of sodium sulfite = 2.80 g

Molar mass of sodium sulfite = 126 g/mol

Putting values in above equation, we get:

$\text{Moles of sodium sulfite}=\frac{2.80g}{126g/mol}=0.022mol$

For a:

Moles of sodium ions in sodium sulfite = (2 × 0.022) moles

According to mole concept:

1 mole of a compound contains $6.022\times 10^{23}$ number of particles

So, 0.022 moles of sodium sulfite will contain = $(2\times 0.022\times 6.022\times 10^{23})=2.65\times 10^{22}$ number of sodium ions

Hence, the number of sodium ions in given amount of sodium sulfite are $2.65\times 10^{22}$

For b:

Moles of sulfite ions in sodium sulfite = (1 × 0.022) moles

According to mole concept:

1 mole of a compound contains $6.022\times 10^{23}$ number of particles

So, 0.022 moles of sodium sulfite will contain = $(1\times 0.022\times 6.022\times 10^{23})=1.325\times 10^{22}$ number of sulfite ions

Hence, the number of sulfite ions in given amount of sodium sulfite are $1.325\times 10^{22}$

For c:

Molar mass of sodium sulfite = 126 g/mol

According to mole concept:

$6.022\times 10^{23}$ number of formula units are present in 1 mole of a compound

Or, $6.022\times 10^{23}$ number of formula units of sodium sulfite have a mass of 126 grams

So, 1 formula unit of sodium sulfite will have a mass of = $\frac{126}{6.022\times 10^{23}}\times 1=2.09\times 10^{-22}g$

Hence, the mass of one formula unit of sodium ions is $2.09\times 10^{-22}$ grams

7 0

3 years ago

Which have more molecules ? 20 g of ammonia or 30 g of oxygen gas?

hodyreva [135]

I think it's oxygen gas

5 0

2 years ago

Read the false statement.

liq [111]

Answer:

The second one is the correct statement.

Explanation:

An atom consists of a dense, heavy, positively charged central part called nucleus. It consists of neutrons and protons.

The electrons revolves around the nucleus in circular paths. These electrons are called planetary electrons because they can be compared to various planets revolving around the sun and the nucleus is compared with sun.

3 0

2 years ago