Question

5 a magnet would be most useful for separating which of these mixtures?
a iron filings of various sizes
b iron filings and cotton fibers
c cotton fibers and grass clippings
d glass marbles and cork pieces
6 kevin pours milk into a bowl of cereal. when the cereal mixes with milk, which property of the cereal changes?
a the mass of the cereal
b the vitamins and other nutrients in the cereal
c the texture of the cereal
d the number of pieces of cereal
7 the science teacher has a mixture of rubber and sand. the teacher says that the two materials have different relative densities, so the mixture can be separated by placing it in a tank of water. when the mixture is poured into the water, where will the sand be located?
a at the bottom of the tank
b throughout the entire tank, mixed into the water
c floating on top of the water
d clinging to the glass walls of the tank

Explanation:

Step1: Analyze question 5

Magnets attract iron. Iron filings can be separated from non - magnetic cotton fibers using a magnet. Options A has only iron filings (no separation), C and D have no magnetic materials.

Step2: Analyze question 6

When cereal mixes with milk, the dry and crunchy texture changes to a softer, soggy texture. Mass, nutrients and number of pieces don't change due to mixing with milk.

Step3: Analyze question 7

Sand has a higher density than water and rubber. Objects with higher density than water sink, so sand will be at the bottom of the tank.

Answer:

1. B. iron filings and cotton fibers
2. C. the texture of the cereal
3. A. at the bottom of the tank