A gold sample contains 90% of gold and the re | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) The mass of the gold sample is $1 \, g$.Since the sample contains $90\%$ gold, the mass of gold present is $0.9 \, g$.The atomic mass of gold $(Au

Vedclass · Accepted Answer

$2.77 	imes 10^{21}$

Vedclass · Answer

(B) The mass of the gold sample is $1 \, g$.Since the sample contains $90\%$ gold, the mass of gold present is $0.9 \, g$.The atomic mass of gold $(Au)$ is approximately $197 \, g/mol$.The number of moles of gold is calculated as: $	ext{moles} = \frac{	ext{mass}}{	ext{atomic mass}} = \frac{0.9 \, g}{197 \, g/mol} \approx 0.004568 \, mol$.The number of atoms is calculated by multiplying the number of moles by Avogadro's number $(N_A = 6.022 	imes 10^{23} \, atoms/mol)$: $	ext{Number of atoms} = 0.004568 	imes 6.022 	imes 10^{23} \approx 2.75 	imes 10^{21} \approx 2.77 	imes 10^{21}$ atoms.

$A$ gold sample contains $90\%$ of gold and the rest copper. How many atoms of gold are present in one gram of this sample of gold?

Similar Questions

Which amongst the following has a greater number of atoms,$11.5 \, g$ of sodium $(Na)$ or $15 \, g$ of calcium $(Ca)$? How? (Given: atomic mass of $Na = 23 \, u$,$Ca = 40 \, u$)

Differentiate between:
$(i)$ Molar mass and Avogadro's constant.
$(ii)$ Molecular mass and formula unit mass.

$(a)$ An atom is considered electrically neutral. Explain.
$(b)$ State the valency of Helium.
$(c)$ If an atom has an atomic mass of $4$ and $2$ protons in its nucleus,how many neutrons does it have?

State whether the following statement is true or false:
$A$ mole always represents $6.023 \times 10^{22}$ atoms,molecules,or ions of a substance.

How did Berzelius assign symbols to the elements?

Vedclass Test Series

Exam Paper Generator

Online Exam Module