6.11 random questions units 1-5

1. What is chemistry?

The study of chemicals

The study of matter and how it changes

The art of mixing chemicals together and the determination of the products that form

A measure of the compatibility between two people

chemistry is the study of matter and how it changes.

Explanation

chemistry is the study of matter and how it changes.

2. What is a substance?

A single chemical or a mixture of chemicals

Two or more atoms bonded together

Any small sample which has been chemically investigated

A pure form of matter

A substance is a pure form of matter.
It many be a single element or atom (in which case there are no bonds), it cannot be a mixture.

Explanation

A substance is a pure form of matter.
It many be a single element or atom (in which case there are no bonds), it cannot be a mixture.

3. Which observation is an example of a physical property?

Dynamite explodes

Meat rots if it is not refrigerated

Gasoline burns

Ice floats on top of liquid water

A silver platter tarnishes

all are forming new substances except the ice floating- no chemical change there.

Explanation

all are forming new substances except the ice floating- no chemical change there.

4. The electron was first proposed to exist based primarily on the results of which experiment?

Thomson's cathode ray tube experiment

Rutherford's gold foil experiment

Bohr's interpretation of the balmer formula

Frankensteins Transylvania experiments with lightning and corpses

Thomson correctly interpreted the cathode ray tube as containing a beam of electrons based on its magnetic and physical properties, the most important being that the beam consisted of particles one thousand times less massive than a hydrogen atom.

Explanation

Thomson correctly interpreted the cathode ray tube as containing a beam of electrons based on its magnetic and physical properties, the most important being that the beam consisted of particles one thousand times less massive than a hydrogen atom.

5. Which key experiment or observation resulted in the concept that electrons reside in shells?

Thomson's cathode ray tube experiment

Rutherford's gold foil experiment

Bohr's interpretation of the Balmer Formula as it relates to atomic emission spectra

Professor Utonium's experiments with chemical x. leading to the creation of the power puff girls

The Balmer formula predicts the sharp wavelengths of light created by ionized hydrogen gas. Balmer interpreted the two integers required to solve the formula as inner and outer shell that an electrons passes between that creates those precise wavelengths of light.

Explanation

The Balmer formula predicts the sharp wavelengths of light created by ionized hydrogen gas. Balmer interpreted the two integers required to solve the formula as inner and outer shell that an electrons passes between that creates those precise wavelengths of light.

6. How many significant figures are there in the following number? 40

4

3

2

1

The zero here is also insignificant because it only tells how far away from the decimal point the 4 is. Had there been a decimal point, there would have been two significant figures.

Explanation

The zero here is also insignificant because it only tells how far away from the decimal point the 4 is. Had there been a decimal point, there would have been two significant figures.