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year 9 Science Homework Week 3

Last updated over 4 years ago
19 questions
1

Who developed the atomic model adding that electrons orbit the nucleus at specific distance?

1

What is the maximum number of electrons in the first shell?

1

What is the maximum number of electrons in the second shell?

1

Magnesium has 12 electrons. How many electrons will magnesium have in its 1stshell?

1

Magnesium has 12 electrons. How many electrons will magnesium have in its 2nd shell?

1

Magnesium has 12 electrons. How many electrons will magnesium have in its 3rd shell?

1

What do carbon-12, carbon-13 and carbon-14 all have in common?

1

What is different about carbon-12, carbon-13 and carbon-14?

1

An isotope is…

1

How will adding neutrons to carbon-12 change it?

1

What is the correct calculation to find the relative atomic mass of an atom?

1

What is the difference between the isotopes helium – 4, helium – 3, and helium – 5?

1

Hydrogen-1 has 0 neutrons, hydrogen-2 has 1 neutron. How many neutrons does hydrogen-3 have?

1

What did scientists use to order elements by?

1

A.What is the correct definition on an element?

1

A.What is a period on the periodic table?

1

What is a vertical column on the periodic table?

1

Approximately how many elements are there?

1

D.What is a substance composed of only one type of atom?