Material World

Question 1

bases have a pH of what on the pH scale?

Answer 1

7.1-14

Question 2

neutrals have a pH of what on the pH scale

Answer 2

7

Question 3

The charge of an atom is based on what

Answer 3

The number of protons and electrons it has

Question 4

is the ion positive or negative if the number of protons is greater than the number of electrons

Answer 4

+ion

Question 5

is the ion positive or negative if the number of electrons is greater than the number of protons

Answer 5

-ion

Question 6

how does an aqueous solution conduct electricity

Answer 6

when a compound is added to it, The compound will separate into two separate charges when dissolved in water

Question 7

what is needed for combustion

Answer 7

heat
fuel
oxidizing agent (usually oxygen)

Question 8

what is the equation for combustion

Answer 8

CH4+2O2—>2H2O+CO2

Question 9

what are three reactions of the carbon cycle

Answer 9

photosynthesis, respiration, and combustion

Question 10

what is the equation for respiration

Answer 10

C6H12O6+6O2—>6CO2+6H2O

Question 11

what is the reaction of photosynthesis

Answer 11

6CO2+6H2O—>C6H12O6+6O2

Question 12

what are periods on the periodic table

Answer 12

The different rows

Question 13

what’s common about each element in a period

Answer 13

they have same number of electrons shells

Question 14

what are the groups on the periodic table

Answer 14

The different columns

Question 15

what does each group have in common

Answer 15

same number of valence electrons

Question 16

where are noble gases located

Answer 16

eighth group

Question 17

where are halogens located

Answer 17

seventh group

Question 18

where are alkaline metals located

Answer 18

first group

Question 19

where are alkali earth metals located

Answer 19

Second group

Question 20

which family is stable

Answer 20

Noble gases

Question 21

which families are highly reactive

Answer 21

halogens and alkali metals

Question 22

what does the Rutherford-Bohr atomic model show

Answer 22

The nucleus with protons only and electrons per shell

Question 23

Protons have a _____ charge

Answer 23

positive

Question 24

Electrons have a ______charge

Answer 24

negative

Question 25

Neutron have _____ charge

Answer 25

no

Question 26

objects with the same charges will _____ each other

Answer 26

repel

Question 27

Objects with opposite charges will _____ each other

Answer 27

attract

Question 28

what is static electricity

Answer 28

it's the transfer of electrons from one body to another

Question 29

what are the three ways you can conduct static electricity

Answer 29

friction, conduction, and induction

Question 30

what is friction

Answer 30

two materials rubbing together and their electrons transfer from one and other

Question 31

what is conduction

Answer 31

when two materials touch each other and the electrons transfer

Question 32

what's induction

Answer 32

when two materials approach each other and their electrons jump from one material to another

Question 33

what is Ohm's law

Answer 33

V=IR

Question 34

what is a direct current

Answer 34

The electrons are flowing in one direction

Question 35

what is an alternating current

Answer 35

when the electrons flow back and forth many times per second in a regular pattern

Question 36

what are the two poles in every magnet

Answer 36

North and south

Question 37

like poles ____

Answer 37

repel

Question 38

opposite poles _____

Answer 38

attract

Question 39

what does the thumb do in the left-hand rule of an electromagnet

Answer 39

points in the direction of current (negative to positive)

Question 40

what do the fingers do in the left-hand rule

Answer 40

they curl in the direction of the magnetic field lines

Question 41

how can you modify the intensity of a magnetic field with an electromagnet

Answer 41

The type of wire and the current intensity

Question 42

what is the law of conservation of energy

Answer 42

Energy cannot be created nor destroyed; it could only be transformed or transmitted

Question 43

The total amount of energy within a closed system always remains what

Answer 43

equal

Question 44

what is the equation for energy efficiency

Answer 44

amount of useful energy/amount of energy consumed x100

Question 45

acids have a pH of what on the pH scale?

Answer 45

0-6.9