Purchase Solution

The Composition of Gold

Not what you're looking for?

Ask Custom Question

You have a piece of gold jewelry weighing 8.5 grams. Its volume is 0.64 cubic centimeters. Assume that th metal is an alloy of gold and copper, which have densities of 19.3 g/cm^3 and 8.5 g/cm^3 respectively. Also assume that there are no changes in volume when the metals are mixed. First, calculate the percentage of gold by volume. Next, calculate the percentage of gold by mass in the piece of jewelry. The relative amount of gold by mass is measured in karats. Pure gold is 24 karat gold. An alloy that is 50% (by mass) gold is 12 karats. State the composition of gold in the jewelry in karats.

a. 17.6 karats
b. 15.4 karats
c. 16.8k
d. 11.2 karats
e. 18.9 karats.

Purchase this Solution

Solution Summary

This posting contains solution to the composition of gold

Solution Preview

First: let x = volume of gold and y = volume of copper. We will form 2 equations:
x + y = 0.64
19.3x + 8.5y = 8.5

Using substitution y = 0.64-x ...

Purchase this Solution

Free BrainMass Quizzes
Organic Chemistry Naming: Alkanes

This is a quiz which is designed to assist students with learning the nomenclature used to identify organic compounds. This quiz focuses on the organic compounds called Alkanes.

Match Elements with their Symbols

Elements are provided: choose the matching one- or two-letter symbol for each element.


The quiz helps in revising basic concepts about thermochemistry.

Functional groups in Organic Chemistry

You will be tested on the names of functional groups in Organic Chemistry. It is very important to know the functional groups to understand Organic reactions.

General Chemistry - Classification of Matter

This test will assess your knowledge on the classification of matter which includes elements, compounds and mixtures.