A customer buys a gold jewellery, he is told that the jewellery has 90% gold and the rest copper. He is given a bill which amounts 100% charges of gold. The customer refuses to pay the bill for 100% gold but brings it to 90% gold amount and settles the bill.
(a) How many atoms of gold are present in 1 gram of gold?
(b) What is the ratio of gold and copper in the jewellery?
(c) What value of customer is reflected in the above statement?
(a) one gram of gold will contain \(\frac{90}{100}\)
= 0.9 g of gold.
∴ Number of mole of gold = \(\frac{Mass\;of\;gold}{Atomic\;mass\;of\;gold}\)
= \(\frac{0.9}{197}\) = 0.0046
∴ 0.0046 mole of gold will contain = 0.0046 x 6.022 x \(10^{23}\)
= 2.77 x \(10^{21}\) atoms
(b) Ratio of gold : copper = 90 : 10
(c) Values of customer are responsible behaviour and self-awareness.