Yr10 summer hw

Question 1

order these of increasing size : organ, tissue, cell, system

Answer 1

cell, tissue, organ, system

Question 2

what is an emzyme?

Answer 2

a protein molecule that acts as a biological catalyst

Question 3

which emzyme breaks down starch?

Answer 3

amylase

Question 4

what small molecule are proteins made of?

Answer 4

amino acids

Question 5

what is the test for sugars?

Answer 5

add benedicts reagent and heat

Question 6

what is meant by an emzyme being “denatured”?

Answer 6

active site has changed shape so substrate no longer fits

Question 7

which scientist conducted the gold leaf experiment to determine the nuclear model of an atom?

Answer 7

Rutherford

Question 8

what is an isotope?

Answer 8

an atom of an element with a different number of neutrons

Question 9

what does atomic number tell you about an atom?

Answer 9

the number of protons (and electrons)

Question 10

what does atomic mass tell you about an atom?

Answer 10

the number of protons plus the number of neutrons

Question 11

what is emitted from the nucleus in alpha decay?

Answer 11

2 protons and 2 neutrons (alpha particle)

Question 12

what material can absorb radiation?

Answer 12

aluminium

Question 13

which type of radiation is the most ionizing?

Answer 13

alpha

Question 14

what is the formula of a hydroxide ion?

Answer 14

OH-

Question 15

what is the name given to an atom or ion gaining electrons?

Answer 15

reduction

Question 16

what is a displacement reaction?

Answer 16

a more reactive metal takes the place of a less reactive metal in a compound

Question 17

what salts are produced when hydrochloric acid reacts with a substance?

Answer 17

chlorides

Question 18

draw the circuit symbol for an ammeter

Answer 18

—-(A)—-

Question 19

draw the circuit symbol for an LED

Answer 19

^^
//
— >|—

Question 20

state the equation the links current, potential difference, and resistance

Answer 20

PD=current x resistance

Question 21

what happens to current in a series circuit?

Answer 21

it is the same through each componemt

Question 22

what happens to current on a parallel circuit?

Answer 22

the total current in the circuit is the sum of the currents through each branch

Question 23

what is the name given to a chemical reaction that takes in thermal energy from the surroundings?

Answer 23

endothermic

Question 24

what is meant by activation energy?

Answer 24

the minimum energy required for a reaction to take place

Question 25

how is the temp change calculated?

Answer 25

max / min temp - initial temp

Question 26

the number of protons and neutrons in the beryllium atom?

Answer 26

P = 4 N=5

Question 27

what is the relative charge on a beryllium ion?

Answer 27

+2

Question 28

what state of matter is shown in box C F3?

Answer 28

gas

Question 29

what is the process when state B(liquid) changes into A(solid)?

Answer 29

freezing

Question 30

how can state B be changed into C?

Answer 30

heat/evaporate/boil

Question 31

who was the existence of the neutron discovered by?

Answer 31

chadwick

Question 32

suggest a limitation of using a ball and stick model for a water molecule

Answer 32

not to scale, not 3D, incorrect arrangement in space, electrons/shells not shown

Question 33

ice has a low melting point because the intermolecular forces are _____.

Answer 33

weak

Question 34

(1 oxygen, 4 hydrogen, 1 carbon) shown in the image what is the molecular formula?

Answer 34

CH40

Question 35

what is the number of bonds formed by each carbon atom in diamond?

Answer 35

4

Question 36

give 2 physical properties of diamond

Answer 36

very hard, very high melting point, does not conduct electricity

Question 37

name 2 other substances with giant covalent structures

Answer 37

graphite, silicon dioxide