atomic structure

Question 1

Which particles are in the nucleus?

Answer 1

protons and neutrons

Question 2

what charge do protons, neutrons and electrons have?

Answer 2

Protons positive, neutrons neutral, electrons negative

Question 3

What does the atomic number tell you?

Answer 3

Number of protons (= number of electrons)

Question 4

What does mass number tell you?

Answer 4

Total of protons + neutrons.

Question 5

Which number is bigger, atomic number or mass number? Which is at the top, which at the bottom?

Answer 5

Mass is bigger, at top. Atomic is smaller, at bottom

Question 6

What is the mass of an electron?

Answer 6

Almost nothing. Often given as 1/2000

Question 7

What is the link between elements in the same group of the periodic table?

Answer 7

They all have same number of electrons in outer shell. So have similar chemical properties

Question 8

If an element has 15 electrons, what is its electron configuration? What is the element?

Answer 8

2, 8, 5 Phosphorus

Question 9

What are isotopes?

Answer 9

Different atomic forms of the same element. Same number of protons, different number of neutrons (so different mass)

Question 10

How do you work out relative atomic mass for two or more isotopes?

Answer 10

1. Multiply atomic mass of each isotope (top number) by relative abundance (given to you). 2. Add those together 3. Divide by sum of relative abundances.

Question 11

How do you work out relative formula mass?

Answer 11

1. Find the atomic mass for each element in the compound 2. Add them together 3. Multiply if there is more than one molecule of each eg RFM of CO2 is: (1 x 12) + (2 x 16) = 44

Question 12

How do you work out empirical formulae?

Answer 12

1. List all elements in the compound 2. Write experimental masses or percentages under each one (found in the experiment) 3. Divide each mass or percentage by atomic mass 4. Results tell you proportions of elements in the compound