All categories

3 years ago

Calculate in witch material - sodium or zinc sulphide is the highest percentage by mass of sulfur

Chemistry

1 answer:

rjkz [21]3 years ago

5 0

Answer:

sodium sulphide.

Explanation:

First, let us obtain the percentage of sulphur in both compounds. This is illustrated below:

For sodium sulphide(Na₂S):

Molar Mass of Na₂S = (23x2) + 32 = 46 + 32 = 78g/mol

Percentage of sulphur in Na₂S is given by:

32/78 x 100 = 41%

For zinc sulphide(ZnS):

Molar Mass of ZnS = 65.4 + 32 = 97.4g/mol

Percentage of sulphur in ZnS is given by:

32/97.4 x 100 = 33%

From the results obtained sulphur has the highest percentage by mass in sodium sulphide.

You might be interested in

Which of the following can be reduced by the use of renewable energy sources

IrinaK [193]

Social cost, Economic costs and Environmental Costs could be reduced by using Renewable energy sources like Hydro Power, Solar Power, Wind Power, Biomass and Geothermal plants. They can provide sustainable energy services since they are available all of the time. They known to have less impacts on various aspects especially in the environmental aspect comparing it to nonrenewable resources like fossil fuel based power plants.

8 0

3 years ago

How many significant figures are in the measurement 0.03050

faltersainse [42]

There are 4 significant figures(3050)

8 0

3 years ago

Excess magnesium reacts with 165.0 grams of hydrochloric acid in a single displacement reaction.

JulsSmile [24]

Answer:

The volume of hydrogen gas produced will be approximately 50.7 liters under STP.

Explanation:

Relative atomic mass data from a modern periodic table:

H: 1.008;
Cl: 35.45.

Magnesium is a reactive metal. It reacts with hydrochloric acid to produce

Hydrogen gas $\rm H_2$ , and
Magnesium chloride, which is a salt.

The chemical equation will be something like

$\rm ?\;Mg\;(s) + ?\;HCl \;(aq)\to ?\;H_2 \;(g)+ [\text{Formula of the Salt}]$ ,

where the coefficients and the formula of the salt are to be found.

To determine the number of moles of $\rm H_2$ that will be produced, first find the formula of the salt, magnesium chloride.

Magnesium is a group 2 metal. The oxidation state of magnesium in compounds tends to be +2.

On the other hand, the charge on each chloride ion is -1. Each magnesium ion needs to pair up with two chloride ions for the charge to balance in the salt, magnesium chloride. The formula for the salt will be $\rm MgCl_2$ .

$\rm ?\;Mg\;(s) + ?\;HCl\;(aq) \to ?\;H_2 \;(g)+ ?\;MgCl_2\;(aq)$ .

Balance the equation. $\rm MgCl_2$ contains the largest number of atoms among all species in this reaction. Start by setting its coefficient to 1.

$\rm ?\;Mg\;(s) + ?\;HCl\;(aq) \to ?\;H_2 \;(g)+ {\bf 1\;MgCl_2}\;(aq)$ .

The number of $\rm Mg$ and $\rm Cl$ atoms shall be the same on both sides. Therefore

$\rm {\bf 1\;Mg}\;(s) + {\bf 2\;HCl}\;(aq) \to ?\;H_2 \;(g)+ {1\;\underset{\wedge}{Mg}\underset{\wedge}{Cl_2}}\;(aq)$ .

The number of $\rm H$ atoms shall also conserve. Hence the equation:

$\rm {1\;Mg}\;(s) + {2\;\underset{\wedge}{H}Cl}\;(aq) \to {\bf 1\;H_2 \;(g)}+ {1\;MgCl_2}\;(aq)$ .

How many moles of HCl are available?

$M(\rm HCl) = 1.008 + 35.45 = 36.458\;g\cdot mol^{-1}$ .

$\displaystyle n({\rm HCl}) = \frac{m(\text{HCl})}{M(\text{HCl})} = \rm \frac{165.0\;g}{36.458\;g\cdot mol^{-1}} = 4.52576\;mol$ .

How many moles of Hydrogen gas will be produced?

Refer to the balanced chemical equation, the coefficient in front of $\rm HCl$ is 2 while the coefficient in front of $\rm H_2$ is 1. In other words, it will take two moles of $\rm HCl$ to produce one mole of $\rm H_2$ . $\rm 4.52576\;mol$ of $\rm HCl$ will produce only one half as much $\rm H_2$ .

Alternatively, consider the ratio between the coefficient in front of $\rm H_2$ and $\rm HCl$ is:

$\displaystyle \frac{n(\text{H}_2)}{n(\text{HCl})} = \frac{1}{2}$ .

$\displaystyle n(\text{H}_2) = n(\text{HCl})\cdot \frac{n(\text{H}_2)}{n(\text{HCl})} = \frac{1}{2}\;n(\text{HCl}) = \rm \frac{1}{2}\times 4.52576\;mol = 2.26288\;mol$ .

What will be the volume of that many hydrogen gas?

One mole of an ideal gas occupies a volume of 22.4 liters under STP (where the pressure is 1 atm.) On certain textbook where STP is defined as $\rm 1.00\times 10^{5}\;Pa$ , that volume will be 22.7 liters.

$V(\text{H}_2) = \rm 2.26288\;mol\times 22.4\;L\cdot mol^{-1} = 50.69\; L$ , or

$V(\text{H}_2) = \rm 2.26288\;mol\times 22.7\;L\cdot mol^{-1} = 51.37\; L$ .

The value "165.0 grams" from the question comes with four significant figures. Keep more significant figures than that in calculations. Round the final result to four significant figures.

5 0

3 years ago

Where do the sun rays hit Earth's surface nearly at right angles

hoa [83]

Answer:

The Sun Ray's hit earths surface at Earths Equator

8 0

2 years ago

1. What is the wave speed of a wave that has a frequency of 100 Hz and a wavelength of 0.30 m?

Sav [38]

Wave speed = frequency x wavelength
= 100 x 0.3
= 30 m/s.

Hope this helps!

5 0

3 years ago

Read 2 more answers

Calculate in witch material - sodium or zinc sulphide is the highest percentage by mass of sulfur ​

Calculate in witch material - sodium or zinc sulphide is the highest percentage by mass of sulfur