gr 10-chemistry (unit 2.4)

Question 1

synthesis reaction

Answer 1

-two or more reactants combine to produce a single product
-most reactions are exothermic
a+b -> ab (+energy)

Question 2

decomposition reaction

Answer 2

-a compound absorbs energy and is broken down into two or more elements or simpler compounds
-it is the reverse of a synthesis reaction
-most reactions are endothermic
ab (+ energy) -> a + b

Question 3

single replacement reaction

Answer 3

• an element and a compound react to replace and produce another element and another compound
• metal element replaces a metal ion in a compound

Question 4

double replacement reaction

Answer 4

-like single replacement except double

Question 5

combustion reaction

Answer 5

-a rapid exothermic reaction in which an element reacts with oxygen to form an oxide of the element and produces heat
a + O2 -> aOx (+energy)
-also refers to the burning of hydrocarbons to produce carbon dioxide and water
-hydrocarbons are compounds made up of just carbon and hydrogen
CxHy + O2 -> CO2 + H2O

Question 6

incomplete combustion

Answer 6

• occurs when the supply of oxygen is too low

- produces products like carbon (soot) and carbon monoxide

Question 7

neutralization reaction

Answer 7

-type of double replacement chemical reaction in wich an acid reacts with a base and they neutralize each other to form a salt and water
HA + BOH -> BA +H2O

Question 8

what do most combustion reactions release?

Answer 8

heat and light

Question 9

What is BC home to?

Answer 9

Karst formations (sinkholes, cakes, streams etc) that result in chemical reactions

Question 10

What does Carbon Dioxide dissolve to in the atmosphere?

Answer 10

rainwater

Question 11

what happens over a time period of thousands of years when rainwater falls and infiltrates the land

Answer 11

Carbonic acid reacts with compounds such as bedrock or limestone that overtime dissolve the rock

Question 12

What are acids?

Answer 12

an acid is a substance that releases hydrogen atoms (H+) in an aqueous solution

Question 13

What are bases?

Answer 13

a base is a substance that releases hydroxide ions (OH-) in aqueous solutions

Question 14

how can you identify if a solution is a base or an acid since it’s usually a colourless solution?

Answer 14

by using an acid-base indicator, PH scale, or litmus paper

Question 15

litmus paper rules

Answer 15

blue litmus paper turns red if its an acid

red litmus paper turns blue if its a base

Question 16

PH scale test rules

Answer 16

ranges from 0-14
if it’s below 7 it’s acidic and if it’s above 7 its a base and if it is 7 it’s neutral
this tells us if there are more, less, or the same amount hydrogen or hydroxide atoms in the solution