Category: Engineering Test Mcqs

A ring contains 2.4 gram of diamond. How many carbon atoms diamond contains?

A. 3.01×10^23
B. 1.2×10^23
C. 1.2×10^22
D. 1.2×1024

Answer

Correct Answer: B. 1.2×10^23


Detailed About MCQs


Use the formula:
N = n *N(A)
In which n = the number of moles, and N(A) is Avogadro’s number, which is 6.02 * 10^23 m^-1.
First of all, the start off by calculating the number of mole Carbon there’s present in the diamond. You got 2.4 grams of the diamond which is made of C atoms. Divide the mass of the diamond with the molar mass of carbon, which is 12.01 g/mole. Hence,
n(C) = 2.4/12.01 = 0.1998 mole
Now, use this formula:
N = n *N(A) => 0.1998 mole * 6,022 * 10^23 mole^-1 = 1.203397169 * 10^23
Hence, the correct answer is Option B.

A ring contains 1.2 gram of diamond, the number of carbon atoms in the ring are____.

A. 6.02 x 10²³
B. 3.01 x 10²²
C. 6.02 x 10²²
D. 1.2 x 10²²

Answer

Correct Answer: C. 6.02 x 10²²


Detailed About MCQs


Use the formula: N = n *N(A)
In which n = the number of moles, and N(A) is Avogrado’s number, which is 6.02 * 10^23 m^-1.
First of all, the start off by calculating the number of mole Carbon there’s present in the diamond. You got 1.2 grams of the diamond which is made of C atoms. Divide the mass of the diamond with the molar mass of carbon, which is 12.01 g/mole.
n(C) = 1.2/12.01 = 0.0999 mole
Now, use this formula:
N = n *N(A) = 0.0999 mole * 6.022 x 10²³ mole^-1 = 0.6015 x 10²³ mole^-1
N = 6.02 x 10²² (10²³ mole^-1 = 10²²)

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