Combining Elements Flashcards
To learn what compunds, elements and mixtures are. Learn what word equations and symbol equations are.
Definition of H2O
It is the element for water, made of 2 hydrogen atoms and 1 oxygen atom
Defintion of CO2
It is the element for carbon dioxide, it is made from 1 carbon atom and 2 oxygen atoms
What is a compund?
A compound is a substance made from different elements chemically joined together
Give the 5 main examples of a compund
E.g--- water E.g--- carbon dioxide E.g--- salt E.g--- chlorine E g--- sodium
How would u draw hydrochloric acid as a molecule atom?
You would draw 1 hydrogen atom connected with a bond with 1 chlorine atom
How would you draw oxygen as a molecule atom? And what kind of bond is it and why?
You would draw it with 2 oxygen atoms connected with a bond between them. This element is an example of a double bond because you are using the same element twice.
What makes up methane? And what is its symbol?
Its made from 4 hydrogen atoms and 1 carbon atom and its symbol is CH4
What is the symbol for sodium chloride and what elements is it made from?
NaCI—> 1 sodium and 1 chlorine
What is the symbol for copper sulphate and what elements make it?
CuSO4—> 1 copper, 1 sulphur and 1 oxygen
What is the symbol for hydrochloric acid and what elements create it?
HCI—> Hydrogen and chlorine
What is the symbol for silver nitrate and what elements are made up of it?
AgNO3—> 1 silver, 1 nitrogen and oxygen
What is ammonia as a symbol?, what elements is it made of and is it a compound or an element?
Symbol— NH3
The elements that make it are 3 hydrogens and 1 nitrogen
It is a compound
What is the symbol for sulfur dioxide?, what are the elements that make it and is it a compound or an element?
Symbol— SO2
Its made up from 2 oxygen and 1 sulfur
Its a compound
What are the reactants and products of calcium carbonate+ hydrochloric acid—> calcium chloride+ carbon dioxide+ water
Reactants= calcium carbonate+hydrochloric acid
Products=calcium chloride+ carbon dioxide+ water
What are the products and reactants of zinc+ copper sulphate—> solid copper+ zinc sulphate
Products= solid copper+ zinc sulphate
Reactants= zinc+ copper sulphate
What are the reactants and products of magnesium+ sulphric acid—> magnesium sulphate+ hydrogen
Reactants= magnesium+ sulphric acid
Products= magnesium sulphate+ hydrogen
What are the reactants and products of magnesium+ water—> magnesium oxide+ hydrogen
Reactants= magnesium+ water
Products= magnesium oxide+ hydrogen
Reactants= magnesium+ water
What is the mass of conservation?
The mass of the products in a chemical reaction must equal the mass of reactants in the equation
What is the mass equation for carbon dioxide?
Carbon= 12g
Oxygen= 16g ×2
Total mass=44g
What’s the formula(symbol) for nitric acid and what is it made from?
HNO3—> made from 1 hydrogen atom, 1 nitrogen atom and 3 oxygen atoms
What is the formula(symbol) for sulphric acid and what is it made from?
H2SO4—> made from 2 hydrogens, 1 sulphur and 4 oxygens
What is iron?
Magnetic, solid, small
What is sulphur?
Non-magnetic, solid, yellow powder
What does iron and sulphur make and how many of each is needed?
1 iron and 2 sulphur molecules when heated up will bond together to form a compound also known as iron sulfide( fool’s gold).
Iron+sulfur—>iron sulfide
Carbon+______ —-> carbon dioxide
Complete the word equation.
Carbon + oxygen—-> carbon dioxide
_______ + oxygen—> iron oxide
Complete the word equation.
Iron + oxygen—> iron oxide
Sulfur+ oxygen—>_______
Complete the word equation
Sulfur + oxygen—> sulfur dioxide
What are the 3 signs that a chemical reaction is taking place?
The change of colour
When you see a difference in temperature
When you can see bubbles/ fizzing occurring
What is the formula of aluninium oxide?
AI203
How would you balance AI + O2—> AI2 03?
You have 1 AI(aluminium) and 2 oxygen for the reactants side and you have 2 AI and 3 oxygen, so you would change the first AI on the reactants side to a 4 AI and 3O2 and then keep 2 AI for the product and keep O3 to have 3 oxygens,now its balanced
Balance N2+ H2—> NH3
You have 2 nitrogens and 2 hydrogens for your reactants and for your products you have 1 nitrogen and 3 Hydrogens so first you change the 1 nitogen in the products by having 2N and keep the 3 hydrogens on that side but then u must change the 2 hydrogens to the 3 hydrogens to 3H2 for the reactants so now you have 2 nitrogens and 6 hydrogens, its balanced
Compelte the word equation.
Sodium hydroxide+hydrochloric acid
NaOH. HCI
--->\_\_\_\_\_\_\_\_\_. + \_\_\_\_\_\_\_\_\_
\_\_\_\_\_\_\_\_\_ \_\_\_\_\_\_\_\_\_Sodium chloride + water
NaCI. H2O
In experiment 1, molly put 2 beakers on a balance. One contained 20cm of hydrochloric acid and other one had 20cm of sodium hydroxide. The total mass was 163.5g. She poured the(hydrochloric) acid onto the sodium hydroxide solution,they reacted but did NOT change(it still read 163.5g),why did the reading not change?
Its because she used the same hydrochloric acid she already had so after it reacted with the sodium hydroxide it wouldn’t have changed beacuse you used the same chemical and measurements she already had, she didnt add anything different.
In experiment 2, molly put 2 beakerson a balance. One contained 20cm of hydrochloric acid. The other contained 5g of sodium carbonate. She poured the (hydrochloric) acid onto the sodium carbonate. They reacted. Complete the word equation with the names of the other 3 products.
Sodium carbonate+ hydrochloric acid—> sodium chloride+carbon dioxide+ water
Pt2:)The total mass at the start was 149.0g. When the reaction stopped,the reading on the balance was 147.0g. Why was there a loss of mass?
Because the gas escaped,which means mass went down
What 3 main columns are diatomic elemants found in the periodic table?
Columns are: 7 and some in 6 and 5
What are diatomic elements?
They are elements that are all found to have pairs e.g nitrogen
What are columns and rows called on a periodic table?
Columns= groups Rows= periods
What is the mass number and what is the atomic number mean in an element?
The mass number is always the biggest number(or the number always on the top)
The atomic number represents how many protons there are.
What are the charges of: a proton, a neutron and an electron?
Proton= +1( positive) Neutron= 0( neutral) Electron= -1(negative)
Describe the element aluminium
Symbol= AI
Group 3
Period= 3
It is a metal, used to make kitchen utensils
Good electrical conductor,silvery hard solid
Describe the element boron
Symbol=B Group= 3 Period=2 Non-metal, hard solid, low density Used to make bullet-proof vests High melting point
Describe the element strontium
Symbol= Sr Group=2 Period= 5 Metal, soft silvery, radioactive Used to make alloys for engineers Good conductor of heat, burns in air
Describe the element calcium
Symbol= Ca Group=2 Period= 4 Metal, soft,reactive Used as a deoxider in steel Dull when exposed to oxygen, found in compunds: limestone, water and marble
Describe the element rubidium
Symbol= Rb Group=1 Period=5 Metal, shiny Used to remove oxygen from vaccum tubes reacts with oxygen in air to be stored as oil
Describe the element lithium
Symbol= Li Group=1 Period= 2 Metal, shiny Used to make lubricants and alloys Cuts easily with a knife Lithium+ water---> lithium hydroxide+ water
Describe the element chlorine
Symbol=CI Group=7 Period=3 Diatomic element, very reactive Yellow-green toxic gas, very low melting point
Describe the element fluorine
Symbol= F Group= 7 Period= 2 Diatomic element, very reactive Used in toothpaste Pale-yellow highly toxic gas Very low melting/boiling point
Describe the element carbon
Symbol=C Group= 4 Period= 2 Non-metal Used to conduct electricity High melting point
Describe the element silicon
Symbol=Si Group= 4 Period= 3 Semi-metal Used in electronics and computers
Describe the element nitrogen
Symbol= N Group= 5 Period= 2 Non-metal Used for ammonia and plant fertilisers
Describe the element phosphorus
Symbol= P Group=5 Period=3 Non-metal Used for plant fertilisers and ends of matches
Describe the element oxygen
Symbol= O Group= 6 Period= 2 Non-metal Used for every living organisim and for burning things
Describe the element sulphur
Symbol= S Group=6 Period = 3 Non-metal Used to make fireworks
Describe the element helium
Symbol= He Group=0 Period= 1 Non-metal Used for baloons
Describe the element Neon
Symbol=Ne
Group= 0
Period= 2
Used in neon signs
Who was Döbreiner and wat did he do?
German scientist,Johan Döbreiner was one of the first to think about grouping elements into sub-groups of 3
An example of his groups are:chlorine,bromine and iodine because they behaved similarly. He calculated that atomic weight of bromine was approximately the same average of chlorine and iodine
His new elements:caesium(1860), fluorine(1886) and geranium(1886) didnt fit into a group so they werent accepted at first.
Who was Newlands and what did he do?
English scientist, who looked at chemical elements from the lowest to the highest ad spotted every eighth element had similiar chemical and physical properties.(1864)
He grouped them into groups of 8
Who was mendeleev and what did he do?
Russian chemist, Dmitri Mendeleev, ranked the elements according to their atomic mass, he lokked fpr repeated pattterns
Where there were no gaps, he was confident in his ideas that not only did he leave a space but predict that had been not yet discovered
The last groups of elements to be discovered were noble gases, this was because they were increative
How do you find the protons, electrons and neutrons in an element?
You find the protons and electrons by using the atomic number( the bottom number) for both and to find the neutron, you subtract the two numbers of the element.
What does the group number tell you?
It tells us how many electrons it has in its outer shell
Why are group 1 metals stored in oil?
Its because if it was to react with oxygen, it would react very strongly.
What happens when lithium reacts with water?
It fizzes, gas is produced and reacts normally
What happens when sodium reacts with water?
It smokes, fizzes and reacts slightly faster
What happens when potassium reacts with water?
It sparks, smokes and reacted the fastest
What happens when calcium reacts with water?
It fizzes, gas is produced and reacts the slowest.
What colour does the water go after all the previous chemicals have reacted with universal indicator?
It turns the colour blue
What is the pattern in this experiment?
The reactivity of group 1 metals used increases as you go down the group.
How much is the first shell worth of electrons?
Its worth 2 electrons
How much after the 2nd shell would it be worth?
It would be worthy of 8 electrons
