Year 8 Science – Solutions and Mixtures 1
Practise comparing states of matter, reading heating and solubility data, calculating density, classifying solutions and planning water clean-up. 20 questions. 25 minutes.
A student pushes the plunger of a sealed syringe. Which sample inside can be squashed into a much smaller volume?
Choose the word that completes each blank.
In a 1, the particles have the weakest attractive forces, so it 2.
Blank 1: solid · liquid · gas
Blank 2: keeps a fixed shape · fills its whole container · has a fixed volume but flows
Two identical bottles of soft drink are opened at the same time. One has been in a fridge and the other in a hot car. Which statement is correct?
Circle 2 words in the sentence below.
Ice is heated until it becomes steam. Click the two temperatures at which the heating curve is flat.
−10 °C0 °C40 °C100 °C120 °C
A student heats substance X at a steady rate and records its temperature. Which statement best explains the readings from 4 to 8 minutes?
| Time (min) | Temperature (°C) |
|---|---|
| 0 | 20 |
| 2 | 40 |
| 4 | 60 |
| 6 | 60 |
| 8 | 60 |
| 10 | 80 |
| 12 | 100 |
Choose the word that completes each blank.
For most solid solutes, solubility 1 as the temperature rises, but for gases such as carbon dioxide, solubility 2.
Blank 1: increases · decreases · stays the same
Blank 2: decreases · stays the same · increases
Sugar sits undissolved on the bottom of a glass of cold water that has been stirred. Which change would allow more sugar to dissolve?
Choose the word that completes each blank.
A solution with very little solute is 1. A solution that holds more solute than normal after being carefully cooled is 2.
Blank 1: concentrated · saturated · dilute
Blank 2: saturated · supersaturated · concentrated
A student stirs spoonfuls of sugar into 100 mL of warm water. The first 12 spoonfuls dissolve, but the 13th stays as crystals on the bottom however long it is stirred. Which word describes the liquid?
Circle 1 word in the sentence below.
A student measures how much of each solute dissolves in 100 mL of water at 20 °C. Click the least soluble solute.
P(32 g)Q(5 g)R(91 g)S(0.2 g)
A solid block has a mass of 54 g and a volume of 20 cm³. What is its density?
How many more grams dissolve in 100 mL of water at 80 °C than at 20 °C?
| Temperature (°C) | Mass dissolved (g per 100 mL) |
|---|---|
| 20 | 32 |
| 40 | 64 |
| 60 | 110 |
| 80 | 170 |
A rock is lowered into a measuring cylinder, raising the water level from 40 mL to 52 mL. The rock has a mass of 30 g. Choose the value that completes each blank.
The volume of the rock is 1 cm³, so its density is 2 g/cm³.
Blank 1: 92 · 1.3 · 12
Blank 2: 2.5 · 0.4 · 360
A metal object has a mass of 142.2 g. It raises the water in a measuring cylinder from 50 mL to 68 mL. What is its density?
Choose the word that completes the blank.
Muddy water is left to stand until the soil settles, then the clear water is poured off. This method is called 1.
Blank 1: filtration · decanting · distillation
Blood is spun in a centrifuge to separate plasma, red blood cells and platelets. Which property difference does this rely on?
Choose the word that completes each blank.
A weakly soluble solute has only a tiny mass dissolved, with the rest sitting on the bottom. The solution is 1 and 2.
Blank 1: saturated · dilute · supersaturated
Blank 2: concentrated · supersaturated · dilute
A coastal town makes drinking water from seawater by distillation. What is the distillate?
Circle 2 words in the sentence below.
Students pollute water with these items. Vinegar and salt are dissolved in the water. Click the two pollutants that a filter can remove.
plasticvinegarsoilsalt
A student pollutes water with plastic pieces, soil and vinegar, then pours it through a gravel, sand and charcoal filter. Which statement is most likely correct?