Atomic Structure

Question 1

What are the 2 observations we made during the gold foil experiment?

Answer 1

1-The beam of alpha particles passed through the gold sheet.

2-The alpha particles scattered.

Question 2

Explain why the alpha particles passed through the gold sheet undeviated.

Answer 2

1-Most of the atom is empty space.

2-The nucleus is tiny.

Question 3

Explain why some alpha particles got deviated with an angle greater than 90?

Answer 3

1-There is a heavy nucleus.
2-The nucleus is tiny.
3-The nucleus is positively charged.

Question 4

Explain why some alpha particles got deviated with angle less than 90?

Answer 4

The nucleus is positively charged.

Question 5

What is the atom made of?

Answer 5

protons (+)
neutrons(no charge)
electrons(-)

Question 6

what is the nucleon number?

Answer 6

number of protons and neutrons in the nucleus.

Question 7

what are the masses of every sub-atomic particle?

Answer 7

protons(1)
neutrons(1)
electrons(1/1840)

Question 8

positive ion

Answer 8

when an atom loses electrons.

Question 9

negative ion

Answer 9

when atom gain electrons.

Question 10

why is the atom neutral?

Answer 10

The number of positive protons are equal of the number of negative electrons.

Question 11

atomic number

Answer 11

number of protons in an atom. (if changed the whole element change)

Question 12

mass number(atomic mass)

Answer 12

number of protons+ neutrons in the nucleus.

Question 13

number of neutrons

Answer 13

mass number-atomic number

Question 14

Isotopes

Answer 14

Atoms of the element with the same number of protons and different number of neutrons.

Question 15

what happens when an isotope is unstable?

Answer 15

it emits radiations until it achieves stability.

Question 16

what type of radiation does an atom emit when becoming stable?

Answer 16

Alpha, Beta, and Gamma.