Mixtures and Solutions

How can a scientist safely tell whether an unknown solution is salt in water or sugar in water?

• taste the solution

• smell the solution

• test the electrical conductivity of the solution

• filter the solution

If two unidentified solids of the same texture and color have different solubility in 100 grams of water at 20C, you can conclude that...

• They are the same

• They are different

• They have different melting points

• The solubility will be the same if the water temperature is increased.

When a solid compound dissolves in water, …

• each of its particles are surrounded by water molecules.

• its particles surround individual water molecules.

Tags

NGSS.MS-PS1-2

What does it mean if a compound has a solubility of 15g in 100g of water at 0C?

• 100g of the compound will dissolve in 15g of water at 0C.

• 15g of the compound will dissolve in 100g of water at 0C.

• The compound will not dissolve until 15g of it are present.

• The compound will dissolve only if the water temperature is 0C.

Table sugar and table salt are examples of ...

• atoms

• elements

• mixtures

• compounds

Tags

NGSS.MS-PS1-1

Substances that cannot be broken down chemically into other substances are...

• elements

• compounds

• mixtures

• solutions

All elements are composed of extremely small particles called..

• compounds

• mixtures

• atoms

• molecules

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-5

Which of these statements is false?

• Oxygen and copper are examples of elements.

• Elements are pure substances.

• Atoms of different elements can combine to form compounds.

• Atoms of different elements are the same.

Weak tea is an example of a...

• dilute solution

• concentrated solution

• suspension

• solvent

When you add so much solute that no more dissolves, you have a

• saturated solution

• unsaturated solution

• neutralization

• suspension