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3 years ago

How many atoms of ca are present in 8.6 mg? the atomic weight of ca is 40.08 amu?

1 answer:

8 0

One mole of any element is Avogadro's number, which is 6.02 * 10^23 atoms. One mole of Calcium is equal to its atomic weight in grams, 1 mole Ca = 40.08 x 1000 mg = 6.02 * 10^23 atoms. We have 8.6mg of Ca which means 8.6mg / 40,080mg = .00021457 of a mole of calcium. Now multiply that by Avogadro's number which gives number of atoms = 0.00021457 * 6.02 * 10^23 atoms. So the answer is 1.292 * 10^20 atoms of Ca.

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B. from 52 moles of nitric acid, how many moles of silver nitrate will be produced?

IceJOKER [234]

Answer:

39 mol AgNO3

Explanation:

We have the equation 4HNO3 + 3Ag -----> 3AgNO3 + NO + 2H2O

We want to calculate the number of silver nitrate (AgNO3) moles that would be produced from 52 moles of nitric acid ( HNO3 )

We can calculate this by using mole ratio as well as dimensional analysis.

The mole ratio of Silver nitrate to nitric acid based on the balanced equation is 3AgNO3:4HNO3.

Using this we can create a table: The table is attached.

Breakdown of the table.

The moles of nitric acid cancel out and we multiply 52 by 3/4 to get 39 moles of Silver nitrate.

6 0

2 years ago

What does the frequency of a wave represent? A. the distance between two consecutive crests B. the number of wave cycles that pa

zepelin [54]

The frequency of a wave represents B. the number of wave cycles that pass through a specific point within a given time.

The distance between two consecutive crests and the length of a wave are the wavelength.

The distance between the highest and lowest points of a wave is twice the amplitude.

6 0

3 years ago

Identify the balanced equation for the following reaction: SO2(g) + O2(g) → SO3(g)

sergiy2304 [10]

Answer: The balanced equation for the given reaction is

$2SO_{2}(g) + O_{2}(g) \rightarrow 2SO_{3}(g)$ .

Explanation:

A chemical equation which contains same number of atoms on both reactant and product side.

For example, $SO_{2}(g) + O_{2}(g) \rightarrow SO_{3}(g)$

Here, number of atoms on reactant side are as follows.

S = 1

O = 4

Number of atoms on product side are as follows.

S = 1

O = 3

To balance this equation, multiply $SO_{2}$ by 2 on reactant side and multiply $SO_{3}$ by 2. Hence, the equation will be re-written as follows.

$2SO_{2}(g) + O_{2}(g) \rightarrow 2SO_{3}(g)$

Here, number of atoms on reactant side are as follows.

S = 2

O = 6

Number of atoms on product side are as follows.

S = 2

O = 6

Now, there are same number of atoms on both reactant and product side. So, this equation is balanced.

Thus, we can conclude that the balanced equation for the given reaction is $2SO_{2}(g) + O_{2}(g) \rightarrow 2SO_{3}(g)$ .

3 0

2 years ago

Aqueous hydrochloric acid will react with solid sodium hydroxide to produce aqueous sodium chloride and liquid water . suppose 1

Aleks04 [339]

The answer is yes I think

5 0

3 years ago

How many grams of phosphorus are in a sample of Ca3(PO4)2 that contains 50.0 g of calcium? Answer: ________ grams of phosphorus.

wel

Answer: The mass of phosphorus that is present for given amount of calcium is 28.53 g.

Explanation:

We are given:

Mass of calcium = 50 grams

The chemical formula of calcium phosphate is $Ca_3(PO_4)_2$

Molar mass of calcium = 40 g/mol

Molar mass of phosphorus = 31 g/mol

In 1 mole of calcium phosphate, 120 grams of calcium is combining with 62 grams of phosphorus.

So, 50 grams of calcium will combine with = $\frac{62}{120}\times 50=28.53g$ of phosphorus.

Hence, the mass of phosphorus that is present for given amount of calcium is 28.53 g.

6 0

3 years ago