Density is the measure of a material's mass per unit volume, used in many aspects of science, engineering and industry. Density can be calculated by dividing an object's mass by its volume. Since different materials have different densities, measuring an object's density can help determine which materials are in it. Finding the density of a metal sample can help to determine its purity.When measuring liquids and regularly shaped solids, mass and volume can be discovered by direct measurement and these two measurements can then be used to determine density. Using a pan balance, determine and record the mass of an object in grams. Using a vernier caliper or ruler, measure the length, depth and width of the object in centimeters. Multiply these three measurements to find the volume in cubic centimeters. Divide the object's mass by its volume to determine its density. Density is expressed in grams per cubic centimeter or grams per milliliter.
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Answer:
8.60 * 
atoms N2
Explanation:
We want to convert grams to moles and then moles to atoms.
First, we convert grams of nitrogen gas (which is N2) to moles. To do so, we need the molar mass of N2, which is just 14.01 * 2 = 28.02 g.
40 g N2 * 
= 1.43 mol N2
Now, we need to convert moles to atoms by using Avogadro's number, which is 
:
1.43 mol N2 * 
= 8.60 * atoms N2
Thus, the answer is 8.60 * atoms N2.
Answer:
Explanation:
a) .0003050 significant figure - 4
b) 432.00 significant figure-5
c) .0000008001 significant figure -4
d) 200608.0 significant figure -7
e) .00001503 significant figure-4
f) 60751.0 significant figure- 6.
zero after decimal are all significant . zero before decimal is significant only when it is preceded by a digit.All digits are significant.
Its in vertical columns. I hope this helps and you get a 100 on your test!
