Science Unit A

Question 1

what is a fluid

Answer 1

any matter that has no fixed shape, can flow and takes the shape of container is a liquid or gas state

Question 2

slurry

Answer 2

combo of a liquid and a solid, easy to transport, use or eat

ex: Slurpee, mud, concrete

Question 3

heterogeneous mixture

Answer 3

a mixture in which all the different substances can be seen when mixing

Question 4

homogeneous mixture

Answer 4

a mixture that looks as if all the substances mixed is just one substance ( you cannot see the different mixtures mixed in)

Question 5

solute

Answer 5

substance that dissolves in a solvent to form a solution e.x is the salt dissolving in water

Question 6

solvent

Answer 6

substance that dissolves a solute to form a solution

e.x. water/ liquids that can dissolve something

Question 7

solubility

Answer 7

ability to dissolve; defined as how much of a solute will dissolve in a particular amount of a solvent.

Question 8

concentration

Answer 8

ability to dissolve the mass of a solute that can dissolve in a given amount of solvent to form a saturated solution at a given temperature (25g/50ML = 50g/100ML)

Question 9

super-saturated

Answer 9

heating beyond saturation point to add more solute than normal. cooling it down keeps it in solution

Question 10

saturated

Answer 10

-cannot add more solute (higher concentration)

Question 11

Unsaturated

Answer 11

• can add more solute (low concentration)

- more diluted

Question 12

what is solubility affected by

Answer 12

type of solvent, type of temp and solute
increased temp= more solute (liquids and solids) dissolved. gases are opposite, increase in temp = decrease in solubility

Question 13

what are the 4 points in the particle model of matter?(sami)

Answer 13

all matter is made up of tiny particles
particles are always moving
particles are attracted to eachother
particles have spaces between them

Question 14

characterize a solid

Answer 14

soilds (most dense)

• most particles
• packed close
• vibrates in place
• strong attractions

Question 15

characterize a liquid

Answer 15

• fewer particles
• more space
• flow/roll over eachother
• shape of container

Question 16

characterize a gas

Answer 16

• least particles
• most energy
• expands to fill space

Question 17

viscosity

Answer 17

the rate of flow of a fluid
fluids measured with ramp test
high vis- molasses. low- water
increased temp, decreased viscosity
low friction, high viscosity 
space affects friction

Question 18

density

Answer 18

amount of mass in a volume (m/v)
least dense= fewer particles in volume
most dense= more particles in small volume
cold temp= more dense particles reduce space and volume decreases

Question 19

buoyancy

Answer 19

opposition force that goes against gravity acting on objects in a fluid (pushes up= floats). equals the displacement of a fluid

Question 20

Plimsoll line

Answer 20

Ships are designed to float in all types of water, regardless of the density of the water. Plimsoll Line- shows how heavily a ship can be loaded in different water conditions.
summer fresh,winter fresh, tropical salt

Question 21

how do hot air balloons work

Answer 21

As the air inside the balloon is heated, it becomes less dense than the surrounding air. The buoyant force of the air will push the hot air balloon upwards, until the buoyant force equals the force of gravity

Question 22

what is pressure and 3 main points

Answer 22

Pressure measures the amount of force applied to a certain area.
Pressure is exerted in all directions
The larger the force, the greater the pressure.
The smaller the area, the greater the pressure.

Question 23

what is Pascal’s Law

Answer 23

Pascal’s Law states that if you apply pressure to fluids that are confined (or can’t flow to anywhere), the fluids will then transmit (or send out) that same pressure in all directions at the same rate.

Question 24

Pump

Answer 24

Moves a fluid through or into something. Ex - Your heart.
Diaphragm pump - changes volume and compresses the air. Archimedes screw - turns to draw water up against gravity. Bike pump - uses a piston (pressure).

Question 25

Diving

Answer 25

When going deep, nitrogen gas can dissolve in the diver’s body cells and tissues in a higher concentration than normal. As the diver rises slowly back to the surface, the nitrogen will leave the body gradually.

Question 26

The Bends

Answer 26

If the diver ascends too quickly the pressure decreases rapidly. As a result the nitrogen gas bubbles out of the blood and tissue, or collects in different parts of the body causing extreme pain. Called → “The bends”

Question 27

treatment for the bends

Answer 27

Treatment for the bends is the use of a hyperbaric chamber, which forces the nitrogen to re-dissolve back into the blood and tissue.