Yr9 Chemistry - Mixtures

Question 1

Define element.

Answer 1

Elements are made form only one type of atom, therefore they are pure.

Question 2

Define compound.

Answer 2

A compound is a pure substance made up of two or more elements chemically joined together.

Question 3

Define mixture.

Answer 3

Mixtures are impure and are made from elements, compounds or elements and compounds, mixtures can be separated easily.

Question 4

Define atomic number and mass number.

Answer 4

The atomic number is the number of protons in the atom. This is also equal to the number of electrons. The mass number is the number of protons plus neutrons in the nucleus.

Question 5

Define atom and sub atomic particle.

Answer 5

The atom is the smallest particle of the element. Sub atomic particles are what makes up the atom, so protons, neutrons and electrons.

Question 6

Define concentration and dilute solution.

Answer 6

A concentration solution has lots of solute dissolved in it. A dilute solution has a little solute dissolved in it.

Question 7

Define pure and impure substances.

Answer 7

Pure substances are made of only one type of atom. For example oxygen. Impure substances are made from two or more particles not chemically joined. For example sand.

Question 8

Define insoluble and soluble and give an example.

Answer 8

Insoluble does not dissolve and soluble does dissolve. For example, sand is insoluble and sugar is soluble.

Question 9

Define solute and solvent and give an example.

Answer 9

Solute is a SUBSTANCE that dissolves and a solvent is the LIQUID that does dissolve. For example, coffee powder is a solute and mil is a solvent.

Question 10

Define periodic table and solution.

Answer 10

The periodic table is a table that organizes the elements based on their atomic number and properties. And a solution is a mixture of solvents and solutes.

Question 11

What is a molecule?

Answer 11

A molecule is a group of atoms bonded together.

Question 12

How many elements are there?

Answer 12

92 elements exist naturally, 24 have been made in labs.

Question 13

What ‘groups’ are there for elements?

Answer 13

Metals, non-metals and metalloids.

Question 14

State the first 20 elements plus the extra ones.

Answer 14

H Hydrogen, He Helium, Li Lithium, Be Beryllium, B Boron, C Carbon, N Nitrogen, O Oxygen, F Fluorine, Ne Neon, Na Sodium, Mg Magnesium, Al Aluminum, Si Silicon, P Phosphorus, S Sulfur, Cl Chlorine, Ar Argon, K Potassium, Ca Calcium, Au Gold, Ag Silver, Cu Copper, Hg Mercury and Fe Iron.

Question 15

What charge do protons, neutrons and electrons have?

Answer 15

Protons = positive, neutrons = neutral and electron = negative.

Question 16

Why are atoms neutral overall?

Answer 16

Atoms are neutral overall because there is the same number as protons(positive) and electrons(negative).

Question 17

What is the shell config on an atom?

Answer 17

2,8,8,2

Question 18

How do groups and periods organize elements?

Answer 18

Groups go up and down and have the same number of electrons in their outermost shell. Periods go left to right and has the same number of electron shells. Elements in the same group or period react similar.

Question 19

What is the name of the outermost shell?

Answer 19

Valence shell.

Question 20

What is the name of the outermost electrons?

Answer 20

Valence electron.

Question 21

Explain dilute, concentration and saturation.

Answer 21

A dilute contains a small amount of solute in a solvent. A concentration contains a large amount of solute in a solvent. A saturated solution is when no more solute will dissolve in a solvent.

Question 22

Explain filtering and decanting separation techniques.

Answer 22

Filtration uses physical properties to separate, it separates solute from solvent based on particle size. Decanting uses time to separate, particles sink to the bottom and then the liquid is poured out, this isn’t precise because the particles can poured out as well.

Question 23

Explain distillation and chromatography separation techniques.

Answer 23

Distillation uses boiling points to separate, the mixture is heated to the lowest boiling point so one substance can evaporate. Chromatography uses amounts of substances to separate, there are two methods, paper and gas.

Question 24

Explain evaporation and magnetic separation techniques.

Answer 24

Evaporation uses boiling points to separate, because the solvent has a lower boiling point, the solvent is left behind. Magnetic separation uses magnetic properties to separate, it extracts certain materials based on their magnetic power.

Question 25

What is the composition of Boron?

Answer 25

B, 5 protons and electrons, 6 neutrons.

Question 26

How would you separate a bucket full of iron fillings, sand and salt?

Answer 26

Explain each separation technique. Use a magnet to remove the iron fillings, then pour water into the mixture so that the salt will dissolve. Filter the sand and salty-water through a filter, the sand become residue and the salty water will pass through and become filtrate. Finally, evaporate the salty-water so the left over is just iron fillings, sand and salt.

Question 27

What is an isotope?

Answer 27

An atom with a different number of neutrons from it’s element.

Question 28

Define ion

Answer 28

An ion is a charged atom or molecule. It is charged because the number of electrons does not equal the number of protons in the atom or molecule

Question 29

Draw metalloid line

Answer 29

boron bottom left to astatine bottom left. Line double thick to the left minus aluminum and polonium.