# FOCUS KIMIA

Central Chemistry

### How to Search for International Journals on Google Scholar

The author has shared in the previous article about how to create a scientific journal, so now the author will discuss how to search for int...

## Chapter 1 — Pratice Test : Matter (Its Properties and Measurement)

Question 1

The volume of seawater on Earth is about 330,000,000 m3 If seawater is 3.5% sodium chloride by mass and has a density of 1.03 g/mL what is the approximate mass of sodium chloride, in tons, dissolved in the seawater on Earth (1 ton = 2000 lb)

Question 2

The diameter of metal wire is often referred to by its American wire-gauge number. A 16-gauge wire has a diameter of 0.05082 in. What length of wire, in meters, is found in a 1.00 lb spool of 16-gauge copper wire? The density of copper is 8.92 g/cm3.

Question 3

A typical rate of deposit of dust (“dustfall”) from unpolluted air was reported as 10 tons per square mile per month. (a) Express this dustfall in milligrams per square meter per hour. (b) If the dust has an average density of 2 g/cm3, how long would it take to accumulate a layer of dust 1 mm thick?