Properties of matter
How can materials be alike and different?
All materials are made up of atoms or combination of same or different atoms.
What is the most appropriate attire when working in a laboratory?
Lab coat, safety goggles, and closed-toe shoes
What are the steps of the scientific method?
define the problem,gather background,form a hypothesis,make observations,test the hypothesis,draw conclusions.
Joshua uses his thermometer and finds the boiling point of ethyl alcohol to be 75o C. He looks in a reference book and finds that the actual boiling point of ethyl alcohol is 80oC. What is his percent error?
6.25 percent
In what type of mixture are the substances evenly distributed throughout the mixture?
Homogeneous
What changes do heating and cooling cause?
chemical changes in which atoms alter their bonding to form new substances.
When should you wear gloves in the lab?
Always when working in the lab
What is a hypothesis?
a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.
The density of water at 4oC is known to be 1.00 g/mL. Kayla experimentally found the density of water to be 1.075 g/mL. What is her percent error?
7.5 percent
Define mixture.
When two or more substances mix without undergoing any chemical change
How does temperature affect matter?
As the temperature of a solid, liquid or gas increases, the particles move more rapidly.
What should you do if you accidentally spill a chemical on yourself?
Clean it up immediately using the appropriate procedure and notify your supervisor
Why is it important to conduct an experiment in the scientific method?
to prove or disprove questions in ways that will lead to unbiased answers
The Handbook of Chemistry and Physics lists the density of a certain liquid to be 0.7988 g/mL. Taylor experimentally finds this liquid to have a density of 0.7925 g/mL. The teacher allows up to +/- 0.500% error to make an “A” on the lab. Did Fred make an “A”? Prove your answer.
0.79 percent
What are mixtures made up of?
A mixture is composed of different types of atoms or molecules that are not chemically bonded
What things are not made up of matter?
Sunlight,Time,Sound
What should you do if you don’t understand the instructions or procedures in the lab?
Consult the instructor or lab supervisor for clarification
What does it mean to analyze data in the scientific method?
the process of interpreting the meaning of the data we have collected, organized, and displayed in the form of a table or graph.
An object has a mass of 35.0 grams. On Anthony’s balance, it weighs 34.85 grams. What is the percent error of his balance?
0.43 percent
What are 2 types of mixtures?
heterogeneous and homogeneous.
What are the 4 states of matter?
Sold,liquid,gas,plasma
When should you remove your safety goggles in the lab?
Never remove your safety goggles while in the lab
Why is communicating the results important in the scientific method?
to maintain trust in the research process and its outcomes
Jessie estimates the weight of her cat to be 10 pounds. The actual weight of the cat is 13.75 pounds.Find the correct percent error.
-27.3 percent error
A solid is stirred into a liquid and dissolves. Which type of mixture forms?
A solution