All categories

3 years ago

How many atoms of carbon are found in a 30.0 gram sample of the element?

Chemistry

1 answer:

saveliy_v [14]3 years ago

3 0

Answer:

1.50 × 10²⁴ atoms C

Explanation:

Step 1: Define

Molar mass of C - 12.01 g/mol

Avagadro's Number: 6.02 × 10²³ atoms, molecules, formula units, etc.

Step 2: Use Dimensional Analysis

$30.0 \hspace{3} g \hspace{3} C(\frac{1 \hspace{3} mol \hspace{3} C}{12.01 \hspace{3} g \hspace{3} C} )(\frac{6.02(10)^{23} \hspace{3} atoms \hspace{3} C}{1 \hspace{3} mol \hspace{3} C} )$ = 1.50375 × 10²⁴ atoms C

Step 3: Simplify

We are given 3 sig figs.

1.50375 × 10²⁴ atoms C ≈ 1.50 × 10²⁴ atoms C

You might be interested in

At a given temperature the vapor pressure of pure liquid benzene and toluene are 745 torr and 290 torr, respectively. A solution

IRISSAK [1]

Answer:

Vapour pressure of benzene over the solution is 253 torr

Explanation:

According to Raoult's law for a mixture of two liquid component A and B-

vapour pressure of a component (A) in solution = $x_{A}\times P_{A}^{0}$

vapour pressure of a component (B) in solution = $x_{B}\times P_{B}^{0}$

Where $x_{A},x_{B}$ are mole fraction of component A and B in solution respectively

$P_{A}^{0},P_{B}^{0}$ are vapour pressure of pure A and pure B respectively

Here mole fraction of benzene in solution is 0.340 and vapour pressure of pure benzene is 745 torr

So, vapour pressure of benzene in solution = $0.340\times 745 torr$

= 253 torr

7 0

3 years ago

Which of these equations is balanced?

mel-nik [20]

A and b are balanced

4 0

3 years ago

Read 2 more answers

Which atom or ion is the largest? A. K B. K+ C. Ca D. Ca2+ E. Li

pishuonlain [190]

Answer:

A. K

Step-by-step explanation:

Remember the trends in the Periodic Table:

Atomic radii decrease from left to right across a Period.
Atomic radii increase from top to bottom in a Group.
Ionic radii of metal cations are smaller than those of their atoms.

Thus, the largest atoms are in the lower left corner of the Periodic Table.

The diagram below shows that K is closest to the lower left, so it is the largest atom. It is also larger than any of the cations.

5 0

3 years ago

When thermal energy is removed from matter, what happens to the molecules?

Colt1911 [192]

Answer:

Figure it out.

Explanation:

3 0

2 years ago

5) answer is A

Burka [1]

Answer:

A) positive; added

Explanation:

Based on the reaction:

2NaHCO3(s) + 129kJ → Na2CO3(s) + H2(g) + CO2(g)

2 moles of NaHCO3 requires 129kJ to produce 1 mole of Na2CO3, 1 mole of H2 and 1 mole of CO2.

That means, the energy must be added being, thus, an exothermic reaction. The exothermic reactions have ΔH >0.

Thus, right answer is:

A) positive; added

3 0

3 years ago