Experimental Design & Properties of Water U1

Question 1

What is a hypothesis?

Answer 1

A testable explanation or prediction based on the observation and the scientist’s prior knowledge

Question 2

What is a null hypothesis?

Answer 2

A prediction that there is no relationship between two variables.

Question 3

What is an independent variable?

Answer 3

The factor or condition being changed
“the cause”
X-axis

Question 4

What is a dependent variable?

Answer 4

The factor or condition being measured
“the effect”
Y-axis

Question 5

What is a control variable?

Answer 5

A factor or condition that is kept
constant throughout the experiment

Question 6

What is a control group?

Answer 6

This group experiences the same
conditions as the experimental group,
except for the single independent
variable being studied

Question 7

What is a controlled experiment?

Answer 7

done in lab

Question 8

What is a natural experiment?

Answer 8

observing and
analyzing something happening
naturally, out of control of the scientist

Question 9

What is quantitative data?

Answer 9

Based on numbers

Question 10

What is Qualitative data?

Answer 10

Based on Observation

Question 11

What is an atom?

Answer 11

the basic unit of matter.

Question 12

What is an element?

Answer 12

a pure substance
that consists of one type of
atom.

Question 13

What is an atom composed of?

Answer 13

Atoms are composed of three
subatomic particles:

Question 14

What is a Proton?

Answer 14

Positively charged subatomic particle, found in
the nucleus.

Question 15

What is a Neutron?

Answer 15

Subatomic particle with no charge, found in
the nucleus.

Question 16

What is an electron?

Answer 16

Negatively charged subatomic particle, found
outside of the nucleus.

Question 17

What are the first 3 layers of electron shells made of?

Answer 17

1st Orbital: Maximum 2 electrons
2nd Orbital: Maximum 8 electrons
3rd Orbital: Maximum 18 electrons

Question 18

What is an atomic number?

Answer 18

the number of protons in the atom.

Question 19

What is a mass number?

Answer 19

the total number of protons and neutrons in
the nucleus of an atom.

Question 20

What is atomic weight?

Answer 20

the weighted average of the masses of an
element’s isotopes.

Question 21

What is an isotope?

Answer 21

Atoms off the same element that differ in the numbers of neutrons they contain. Identified by mass number.

Question 22

What is a valence shell?

Answer 22

the outer orbital/electron shell.

Question 23

What is a cell?

Answer 23

basic unit of life

Question 24

What is a compound?

Answer 24

a substance formed by the chemical combination of two or more elements in definite proportions.

Question 25

What is a molecule?

Answer 25

made when two or more atoms are chemically bonded together?

Question 26

What are the two types of chemical bonds?

Answer 26

Ionic and Covalent

Question 27

What are ionic bonds?

Answer 27

Chemical bond formed when one or more electrons are transferred from one atom to another.

Question 28

What is an ion?

Answer 28

An atom that either gains electrons or loses electrons. As such, it is either positively or negatively charged.

Question 29

What are covalent bonds ?

Answer 29

Chemical bond formed when the electrons are shared between atoms.

Question 30

What do carbons four valence electrons allow them to do?

Answer 30

bond with many other atoms. As such, chains of carbon often form the backbone of macromolecules.

Question 31

What are macromolecules?

Answer 31

Macromolecules are large molecules made from many smaller molecules.

Question 32

What are Monomers and Polymers?

Answer 32

Monomers: the small units. * Polymers: the large units.

Question 33

What is polarity in a hydrogen molecule?

Answer 33

a water molecule is polar because there is an uneven distribution of electrons between the hydrogen atoms and oxygen atoms. The negative pole is near the oxygen atom and the positive pole is near the hydrogen atoms

Question 34

What are Intramolecular forces?

Answer 34

forces that hold atoms together within a molecule.

Question 35

What are Intermolecular forces?

Answer 35

forces that exist between molecules.

Question 36

what is a hydrogen bond?

Answer 36

attraction between a hydrogen atom and another atom.

Question 37

What is cohesion and adhesion?

Answer 37

attraction of molecules of the same substance. attraction between molecules of different substances.

Question 38

What is Capillary Action?

Answer 38

tendency of water to rise in a thin tube.

Question 39

What is a mixture?

Answer 39

a material composed of two or more elements or compounds that are physically mixed together but not chemically combined.

Question 40

What is a suspension?

Answer 40

mixture of water and nondissolved material

Question 41

What is a solution?

Answer 41

type of mixture in which all components are evenly distributed

Question 42

What are solutes and solvents?

Answer 42

Solute: substance that is dissolved in solution. Ex: sugar, salt Solvent: dissolving substance in a solution. Ex: water

Question 43

What is hydrophobic?

Answer 43

nonpolar molecules that repel water molecules. “Water fearing”

Question 44

What is hydrophilic?

Answer 44

molecules forming ionic or a hydrogen bond with water molecules. “Water loving”

Question 45

What is surface tension?

Answer 45

The surface becomes stronger because they exert more force horizontally when they cant exert it up(happens to water)