All categories

3 years ago

How many grams is 4.2X10^24 atoms of sulfur?

1 answer:

7 0

First find the number of moles of sulfur using dimensional analysis with avogadro’s number as the conversion factor. 4.2*10^24 atoms * (1 mol/6.022*10^23 atoms) = 7.0 mol sulfur. The molar mass of sulfur is 32.06 g/mol, which is found on the periodic table as sulfur’s (S) atomic weight. Use dimensional analysis again with the molar mass of sulfur as the conversion factor. 7.0 mol * 32.06 g/mol = 224.42 g sulfur. Since the problems gives us two significant figures, round the mass of sulfur to 220 grams, or 2.2 * 10^2 g.

You might be interested in

112 g of aluminum carbide react with 174 g water to produce methane and aluminum hydroxide in the reaction shown below.

dolphi86 [110]

Answer: 4.999 moles of excess reactant will be left over.

Explanation:

Limiting reagent is defined as the reagent which is completely consumed in the reaction and limits the formation of the product.

Excess reagent is defined as the reagent which is left behind after the completion of the reaction.

The number of moles is defined as the ratio of the mass of a substance to its molar mass.

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ .....(1)

Given mass of aluminium carbide = 112 g

Molar mass of aluminium carbide = 143.96 g/mol

Putting values in equation 1:

$\text{Moles of aluminium carbide}=\frac{112g}{143.96g/mol}=0.778mol$

For the given chemical reaction:

$2Al_4C_3(s)+12H_2O(l)\rightarrow 3CH_4(g)+4Al(OH)_3(s)$

By the stoichiometry of the reaction:

2 moles of aluminium carbide reacts with 12 moles of water

So, 0.778 moles of aluminium carbide will react with = $\frac{12}{2}\times 0.778=4.668 mol$ of water

Given mass of water = 174 g

Molar mass of water = 18 g/mol

Putting values in equation 1:

$\text{Moles of water}=\frac{174g}{18g/mol}=9.667mol$

Moles of excess reactant (water) left = 9.667 - 4.668 = 4.999 moles

Hence, 4.999 moles of excess reactant will be left over.

8 0

2 years ago

A model of an ideal gas is shown here. A student designs an experiment to test the impact of increasing the pressure on the syst

k0ka [10]

A. As pressure on the gas increases, the volume and temperature will both decrease

6 0

3 years ago

¡¡¡PLEASE HELP!!! I'm stuck on a question..

Reptile [31]

The half life of uranium- 238 is

4.46 x10^9 years

Explanation

Half life is the time taken for the radioactivity of a isotope to fall to half its original value.

The original mass of uranium-238 is 4.0 mg

Half of original mass of uranium = 4.0 mg /2 = 2.0 mg

since it take 4.46 x 10^ 9 years for the sample to half the half life of uranium -238 = 4.46 x10^9 years

7 0

3 years ago

Balance environment is useful for both plants and animals for their survival Why

professor190 [17]

Answer:

In summary, the ecological balance brings the existence of the world. Earth's inhabitants such as human beings, plants, animals and other micro living organisms continue to survive. These species get the conducive environment to multiply and thrive. The world gets to produce sufficient food for all species.

may this help u

6 0

2 years ago

Read 2 more answers

Which of the following would most likely happen if water did not form hydrogen bonds?

Oksanka [162]

Water would not expand when it freezes.

8 0

3 years ago

Read 2 more answers