Chapter 1 - Atomic Structure

Question 1

What is avogadro’s constant?

Answer 1

6.02214086 × 10^23 mol-1

Question 2

How did scientists know the properties of electrons using a cathode-ray tube?

Answer 2

They were deflected greatly by the negatively charged plate, suggesting that it is negatively charged and has a small mass

Question 3

How did scientists know the properties of protons using a cathode-ray tube?

Answer 3

They were deflected by the positively charged plate, but not as strongly as the electrons, showing they are greater mass than electrons and are positively charged

Question 4

How did scientists know the properties of neutrons using a cathode-ray tube?

Answer 4

They were not deflected at all, showing that they have no charge

Question 5

What is the relative mass of an electron?

Answer 5

1/1836

Question 6

What is the definitions of elements?

Answer 6

A substance that cannot be broken down further into simpler substances by chemical means

Question 7

What is the atomic number?

Answer 7

The number of protons in the nucleus of an atom

Question 8

What is the mass number?

Answer 8

The number of protons and neutrons in the nucleus of an atom

Question 9

What is an isotope?

Answer 9

Atoms of the same element that have the same number of protons

Question 10

Are there any changes in properties between isotopes?

Answer 10

Their chemical properties are the same, but physical ones like density or mass may vary

Question 11

What are radioactive isotopes dubbed as?

Answer 11

radioisotopes

Question 12

What are radioactive isotopes used for? (5)

Answer 12

checking leaks in oil or gas pipelines, or checking the thickness of a paper. They can also be used to treat cancer and to check the activity gland in the throat

Question 13

What are the nucleons?

Answer 13

Protons and neutrons