Read the following research question:
Do tomatoes grow fastest under fluorescent, incandescent, or natural light?
What are the independent and dependent variables in the question above?
Independent: type of light
Dependent: rate of growth of the tomato plant
What are the charges of:
1. proton
2. neutron
3. electron
1. +
2. neutral
3. -
Give me a definition of matter?
Anything that has mass and volume!
Is salt water a homogeneous or heterogenous mixture and why?
Is a chocolate chip cookie homogeneous or heterogeneous and why?
homogeneous because the ratio of salt to water is consistent.
Heterogeneous because the ratio of chocolate chip to cookie is inconsistent.
What wavelength can humans see at?
400 -700 nm
On a graph, where do you place the...
1. x-axis
2. y-axis
3. independent variable
4. dependent variable
1. horizontal line at the bottom
2. vertical line along the side
3. x- axis
4. y-axis
Where are electrons located in an atom?
In the surrounding cloud
What is happening to molecules in the 3 states of matter?
solid: no movement
liquid: some movement, week bonds
gas: moving as far as container allows, no bonds
You take 5 grams of sugar and dissolve it in 50mL of sprite.
What is the solute?
What is the solvent?
Solute = sugar
solvent = sprite
What is the relationship between wavelength and frequency?
Inverse relationship. As wavelength increases, frequency decreases. As frequency increase, wavelength decreases.
What is the correct format to use when writing a hypothesis?
If, then, because....
What atoms are located in the nucleus?
protons and neutrons
What are the 2 types of pure substances?
What are the 2 types of mixtures?
compounds and elements
homogeneous and heterogeneous
How can you tell when a solution is saturated?
What happens to the look and taste of a saturated liquid?
Calculate the % of H in HCl3?
H = 1g Cl = 35.5
(mass of element / mass of compound) x 100
When is can no longer dissolve any solvent.
It also gets darker and sweeter.
(1 / (35.5 x 3)) x 100 = 0.9 %
1. trough
2. crest
3. wavelength
4. amplitude
1. bottom of wave
2. top of wave
3. top of wave to top of wave
4. top of wave to ground / neutral
Give 3 observations:
Give me 3 inferences:
In the following sentence, what is the observation and what is the inference?
Sally saw that the mixture created bubbles. The oxygen was reacting with the silver.
bubbles = observation
chemical reaction = inference
You have to look at the periodic table!
16.1
32.1 - 16
On a phase diagram, what does the triple point mean?
What phase is farthest to the right when looking at a phase diagram?
the gas phase
A solution is prepared by mixing 25.5 grams of salt with 450 grams of water. What is the mass percent of salt in the saltwater solution?
mass % = (mass of solute / mass of solvent) x 100
25.5g / (450 + 25.5) x 100 = 5.4%
Calculate for wavelength of a wave that has a frequency of 1.36 x 10^ 8 Hz:
c = (wavelength) (frequency)
c = 3.00 x 10 ^ 8 m/s
You must also have the correct units!!!
wavelength = (3.0 x 10^8) / (1.36 x 10^8) =
0.45 m
Out of the following, which are quantitative?
the house was blue
the house was 15 ft tall
the house looked old
the house smelt like cookies
the house weighted 3000 pounds
3000 pounds
15 ft tall
How many electrons are in Rn?
86 electrons
Which 3 phase changes release energy?
Which 3 phase changes require energy?
Condensation, freezing, deposition
melting, evaporating, sublimation
Cows milk contains 5.6% lactose. Calculate the mass of lactose present in 175 g of milk.
You will have to rearrange the equation!!!
mass % = (mass of solute / mass of solvent) x 100
What is the percent composition of N in NH3?
N = 14 g H = 1 g
(mass of element / mass of compound) x 100
(175g x 5.6%) x 100 = 9.8 g lactose
9.8 g lactose
(14g N / 17 g NH3) x 100 = 82.4% N
Calculate the frequency of a wave with the wavelength of 620 nm. You must have the correct units!!
1m = 10^9 nm
c = (wavelength) (frequency)
c= 3.00 x 10^8
What color has the longest wavelenth?
What color has the shortest wavelength?
620 nm / 10^9 = 6.20 x 10^-7 m
v= (3.0 x 10^8) / (6.3 x 10^-7)
v = 4.8 x 10^14 Hertz!!! (s^-1)
red = longest violet = shortest