1. Why do scientists use the scientific method? *

to answer questions about the natural world
to figure out how to run experiments
to show people they are smart
to collect data

Read the following passage and answer use it to help you answer questions 2 and 3
A student wants to determine the effect of a certain brand of liquid fertilizer on the growth of ivy. Ivy plants of the same length are planted in the same amount of soil in three identical containers. To one container, 5 mL of the fertilizer is added; in the second container, 10 mL of the fertilizer is added; and in the third container no fertilizer is added. The containers are placed in front of the same window. The length of the ivy is measured every five days, and the observations are recorded in a data table.

2. What was the independent variable in this experiment? *

soil
light
fertilizer
growth

3. List at least 1 control variable in the experiment. 1 point

soil
light
fertilizer
growth

A scientist wants to determine if humidity affects chirping in crickets. She makes this table.

4. What is the independent variable? *

Captionless Image
Temperature
Humidty
Number of Chirps

5. A scientist is testing the efficiency of various microwaves by measuring the temperature of water after being heated at high power for one minute. The temperature measured in this test is an example of *

independent variable
dependent variable
control group

6. Which of the following are abiotic factors? (Check all that apply) *

elephant
tree
water
grass
air
bugs
soil

7. What are 2 ways abiotic factors affect biotic factors? (Check all that apply) *

a bird picks food out of an alligators teeth
an alligator submerges itself under water to stay cool in the summer
water is oxygenated
an alligator suns itself on the shore to raise its body temperature.

8. Which property of water allows water molecules to stick to the sides of a drinking straw? *

high heat capacity
strong cohesion
strong adhesion
good solvent
Use this image below to answer question #9. (Oxygen) on the periodic table

9. How many protons AND neutrons are in a stable oxygen atom? *

8
14
12
16

10. Which two particles are found in the nucleus of an atom? (Check all that apply) *

protons
ions
electrons
neutrons

11. What is the difference between an isotope and an ion? (Check all that apply) *

isotopes are atoms with extra electrons or too few electrons
ions are atoms with extra electrons or too few electrons
isotopes are atoms with extra neutrons or too few neutrons
ions are atoms with extra neutrons or too few nuetrons
isotopes are radioactive
ions are radioactive

12. Biology is the study of living things. Carbon is the element that makes life possible. Why is carbon so special that it is required for life? *

It is a positively charged ion needed in reactions.
It has 4 valence electrons, so it can make 4 strong bonds with other atoms.
It is a polar molecule, which makes it have a high heat capacity.
Because it has 4 valence electrons, it is small and only makes small compounds.

13. Covalent bonds are formed when 2 atoms share electrons. Ionic bonds are formed when one atom steals 1 or more electrons from another atom, creating positive and negative ions. These ions now "stick together". Using the table below, which column of elements are more likely to form ionic bonds than covalent bonds? *

Captionless Image
orange and yellow
red and dark purple
orange and blue
red and light purple

14. A compound is a molecule built of 2 or more different elements. How are the properties of the compound related to the properties of the elements that make it? *

The compound has different properties, because the bonds cause structural changes of the elements
The compound has the same properties of the atoms, because the properties of elements don't change
The compound has different properties, because the elements stay the same

15. When a chemical reaction occurs, energy is either used up (absorbed) or released (given off). What is the term that describes a reaction in which there is an explosion of heat and light? *

endothermic
exothermic
ionic
covalent

The aim of scientific method is to answer a question that the scientist have. To answer the question, the scientist need to design a research or observation. If the research is flawed, the result might not match with the scientist aim and the conclusion will be wrong. Scientific method can be used to help design the research so it will have less flaw

2. Answer: fertilizer

The student wants to determine the effect of a certain brand of liquid fertilizer on the growth of ivy. The fertilizer are hoped to influence the growth of the ivy. Independent variable is the variable that hoped to influence the dependent variable. So, the independent variable would be fertilizer.

3. Answer: soil; light

Control variable is the variable that could influence the independent variable, but doesn't want to be observed. Control variable should be made same so it wont influence the result. In this case, the plant use the same amount of soil. The plant also put in front of a same window, so they should get the same amount of sunlight.

4. Answer: Humidty

The scientist wants to determine if humidity affects chirping in crickets. The humidity hoped to affects the chirping in crickets. Independent variable is the variable that hoped to influence the dependent variable. So, the humidity is independent variable while the number of chirping is the dependent variable.

5. Answer: dependent variable

The scientist is testing the efficiency of various microwaves by measuring the temperature of water. The microwaves is hoped to influence the temperature of the water. So, the temperature would be the dependent variable of the experiment and the microwaves will be the independent variable

6. Answer: water; air; soil

Abiotic factor consist of factor that made of non-living things. Water, air and soil is not a living things. Animals like elephant should be clearly living so they are biotic factor. Grass and tree could not move freely like animal and hard to determine if still living or not, but they should be considered as living thing.

7. Answer: an alligator submerges itself under water to stay cool in the summer; an alligator suns itself on the shore to raise its body temperature.

If a bird picks food from alligator teeth, it would be interaction of biotic factor with biotic factors. Alligator trying to control their body temperature by sunbath or submerge would be interaction between abiotic factor(sunlight, water) with biotic factor(alligator). Oxygenated water is interaction between abiotic factor(water) with abiotic factor(air/oxygen).

8. Answer: strong adhesion

Water has high heat capacity which makes it temperature hard to changes. It will need more energy/heat to change the temperature of water when compared to air. Adhesion of water makes it could stick to other things while cohesion makes the water stick to itself. The force that cause molecules of water to stick to the sides of a drinking straw would be adhesion.

9. Answer: 14

oxygen has atomic number 8 and atomic mass of 14. The atomic number show the amount of proton and electron that the oxygen has while the atomic mass show the sum of proton and neutron. The number of protons and neutrons in stable oxygen would be 14, same as the atomic mass.

10. Answer: protons; neutrons

Protons and neutrons could be found in the nucleus of the atom while the electron is orbiting in the outer layer. The mass of the atom mostly contributed by the protons and neutrons while the electron is too small and their mass is negligible.

11. Answer: ions are atoms with extra electrons or too few electrons; isotopes are atoms with extra neutrons or too few neutrons; isotopes are radioactive

When an atom has less electron it will be called cation while the atom with more electron called anion. Isotopes have different number of neutrons which make some of them become radioactive. Isotope should have the same number of electrons.

12. Answer: it has 4 valence electrons, so it can make 4 strong bond with other atoms.

Carbon made most of the organic compound. Carbon can be found in carbohydrate, protein and lipid. It has 4 valence electrons which enable 4 slot of covalent bond with oxygen and hydrogen which allow those 3 molecule to have many type of bonds.

13. Need image to answer

14. Answer: The compound has different properties, because the bonds cause structural changes of the elements

Compound will have different properties compared to the element that makes it. Table salt is made of natrium and chlorine atom. The natrium element will explode when exposed to water while natrium chloride is found most in the sea.

15. Answer: exothermic

Reaction that produce energy will be called exothermic while reaction that absorb energy called endothermic. If the reaction cause light and explosion, then the reaction should produce energy and called exothermic. The ion or compound should have no relation in this.