Question

Chapter 1 – Study Guide

Define macroscopic world and microscopic world.

Why is important for us to think on the atomic level?

Define matter, atom and element.

Can molecules be form by more than one atom of the same element? If so, provides examples.

What is a chemical reaction?

What is the scientific method? What are the steps of the scientific method?

Define each step of the scientific method. What information do we get from each of the step of the scientific method?

Define measurement. What are the parts of a measurement?

What is the SI?

List the fundamentals SI units.

How can the size of an unit be changed?

List the prefixes used on the SI

Define uncertainty on a measurement.

What is an estimated number? What is an uncertain number?

How often does a measurement have a degree of uncertainty?

Define accuracy and precision. Give an example of accuracy and an example of precision.

What are significant figures? How do we know when a figure is significant? List the rules of significant figures. How do we determine significant figures on a mathematical operation: addition, subtraction, multiplication, and division.

How many significant figures are present on 12305, 12370, 0.08709, 0.09.

What are leading zeros? Give an example.

What are captive zeros? Give an example.

What are trailing zeros? Give an example.

What is an exponential notation? Give an example.

What is a dimensional analysis?

What unit (conversion) factor could be use to convert from hours to minutes?

What unit (conversion) factor could be use to convert from years to days?

Define the three temperature scales: Fahrenheit (F), Celsius (C), Kelvin (K).

How do we convert from each temperature scale to the others?

What is density? How can we use the density of a compound and its volume to determine the mass of a compound?

Ho w do we classify matter?

Define gas, solid and liquid.

Define heterogeneous and homogeneous mixtures. Give an example of each.

What is a chemical change? What is a physical change? Give an example of each.

Describe the organization of matter.

Answer 1

Define matter, atom and element.?

matter is defined as any substance which has mass and occupies space.matter can exist in the most common forms of solid, liquid and gas.

matter consists of small particles called atoms.

Atoms are the smallest particles of matter, that we cannot break down further by chemical reactions.

an element consists of only one type of atoms.

example.....Sodium is made of sodium atoms only, so it is an element.

iron rod consists of iron atoms only hence it is an element.

Can molecules be formed by more than one atom of the same element? If so, provides examples.?

yes elements of the same elements can form the molecules like H₂ , F_{2 ,}

O₂ consists of two oxygen atoms only.

What is a chemical reaction?

in a chemical reaction reactants combine and form new products with different properties.

in a chemical reaction atoms rearrange by breaking the bonds in reactant and forming new bonds in products

example 2 H₂ + O₂   ---------------- > 2 H₂O

how do we classify the matter?

matter can be classified into three catogories based on the physical stateof it

solid , liquid and gas

Define gas, solid and liquid?

The particles in a gas are far apart There are very weak forces of attraction holding them together.They move in all directions colliding with one another . they dont have any definete shape or volume.

The particles in a solid are arranged in a fixed pattern and Strong forces hold them together.The only movements they make are vibrations to and fro.solid has a definte volume and definite shape

The particles in a liquid can move from one postion to another .They are still close together The forces that hold them together are weaker than in a solid but greater than gases. liquids have define volume but not definite shape.