1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
garik1379 [7]
2 years ago
5

How many formula units make up 24.2 g of magnesium chloride (MgCl2)? Help!!

Chemistry
1 answer:
NNADVOKAT [17]2 years ago
6 0

Answer:

Approximately 1.53 \times 10^{23} formula units (0.254\; \rm mol).

Explanation:

Refer to a modern periodic table for the relative atomic mass of magnesium (\rm Mg) and chlorine (\rm Cl):

  • \rm Mg: 24.305.
  • \rm Cl: 35.45.

In other words, the mass of 1\; \rm mol of \rm Mg atoms would be (approximately) 24.305\; \rm g.

Likewise, the mass of 1\; \rm mol of \rm Cl atoms would be approximately 35.45\; \rm g.

One formula unit of the ionic compound \rm MgCl_{2} includes exactly as many atoms as there are in the given formula. The formula mass of a compound is the mass of 1\; \rm mol of the formula units of this compound.

The formula \rm MgCl_{2} includes one \rm Mg atom and two \rm Cl atoms.

Hence, every formula unit of \rm MgCl_{2} \! would include the same number of atoms: one \rm Mg\! atom and two \rm Cl\! atoms. There would be 1\; \rm mol of \rm Mg atoms and 2\; \rm mol of \rm Cl atoms in 1\; \rm mol\! of \rm MgCl_{2} formula units.

Thus, the mass of 1\; \rm mol\! of \rm MgCl_{2} formula units would be equal to the mass of 1\; \rm mol of \rm Mg atoms plus the mass of 2\; \rm mol of \rm Cl atoms. (The mass of 1\; \rm mol\!\! of each atom could be found from the relative atomic mass of each element.)

\begin{aligned}& M({\rm MgCl_{2}}) \\ =\; & 24.305\; {\rm g \cdot mol^{-1}} + 2\times {\rm 35.45 \; \rm g \cdot mol^{-1}} \\ =\; & 95.205\; \rm g \cdot mol^{-1}\end{aligned}.

In other words, the formula mass of \rm MgCl_{2} is 95.205\; \rm g \cdot mol^{-1}.

Therefore, the number of formula units in m = 24.2\; \rm g of \rm MgCl_{2} would be:

\begin{aligned}n &= \frac{m({\rm MgCl_{2}})}{M({\rm MgCl_{2}})} \\ &= \frac{24.2\; \rm g}{95.205\; \rm g\cdot mol^{-1}} \\ & \approx 0.254\; \rm mol\end{aligned}.

Multiple n by Avogadro's Number N_{A} \approx 6.022 \times 10^{23}\; \rm mol^{-1} to estimate the number of formula units in 0.254\; \rm mol:

\begin{aligned}N &= n \cdot N_{A} \\ &\approx 0.254\; \rm mol \times 6.022 \times 10^{23}\; \rm mol^{-1} \\ &\approx 1.53\times 10^{23}\end{aligned}.

You might be interested in
A hurricane is a type of serve cyclone which statement best explains how a hurricane forms
storchak [24]

Answer:

Hurricanes form over the warm ocean water of the tropics

Explanation:

when war, moist air over the water rises , it is replaced by cooler air

7 0
3 years ago
Which of the aqueous solution does not conduct electricity ? 1.Ca(NO3)2 / 2.CH3NH2/ 3.CH3OH/ 4.CH3COOH
bezimeni [28]

For an aqueous solution to conduct electricity, ions must be present in solution.

This means soluble salts will conduct electricity. Also, since acids and bases have ions in solution, they could also conduct electricity. Option 1 is a soluble salt. Options 2 and 4 are base and acid respectively. Option 3, though soluble in water, exist as a molecule, therefore its solution cannot conduct electricity.

8 0
3 years ago
What is significant about the temperature absolute zero?
Reptile [31]

Explanation:

The absolute temperature is the lowest possible temperature in the universe. At this temperature, all atoms become motionless and cease to move.

The value of the absolute zero is pegged at -273.16°C.

  • It is the lowest limit of the coldness of a body.
  • Nothing can be colder than a body at absolute temperature.
  • Many researches are underway to take advantage of this temperature value for scientific purpose.
  • Thermodynamically, all process stops at this temperature.
  • When a body is brought close a body at absolute zero, it can suffer cryogenic burn due to heat transfer.
4 0
3 years ago
Metals and their ore​
Maksim231197 [3]

Answer:

Zinc

Zinc blende

(ZnS)

-----------------

Lead

Galena

(PbS)

-----------------

Mercury

Cinnabar

(HgS)

----------------

Copper

Copper glance

(Cu2S)

-------------------

Explanation:

Had to learn this for a test

Also, I plead the 5th

8 0
3 years ago
Shadow club!!!!!!!!!!
pychu [463]
WHATS THATT ???????????????
7 0
3 years ago
Read 2 more answers
Other questions:
  • Which group of factors are most important in determining the composition of ocean water? a.)temperature, salinity, and density b
    14·2 answers
  • Technetium-104 has a half life of 18.0 minutes. how much of a 165.0 g sample remains after 90.0 minutes?
    15·2 answers
  • A drop of water placed on a smooth, dry surface will form a dome-shaped droplet instead of flowing outward in different directio
    5·2 answers
  • 3. In all cells, genetic materials are stored in the
    7·2 answers
  • When copper metal is added to silver nitrate in solution, silver metal & copper (ii) nitrate are produced. What mass of silv
    11·1 answer
  • Find the number of moles in 1.00 x 1023 atoms of chromium.
    15·1 answer
  • The shadow zone exists because ?
    11·1 answer
  • Which three steps describe how an animal obtains and uses energy for growth?
    12·1 answer
  • The strongest bases have pH values close to
    5·1 answer
  • 5.00 moles of a binary, group 2 oxide are found to have a mass of 521 g. Identify the group 2 metal
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!