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KS3 elementcompound
KS3 elements and compounds
Question | Answer |
---|---|
What is an element? | A substance that cannot be split up into anything simpler by chemical reactions |
How many elements do we know about? | 117 elements—90 of which are found naturally. |
What is the proper name for the particles in a substance? | Atoms |
What is the periodic table? | A table showing all the elements in order of atomic mass |
Why is Demitri Mendeleev famous? | He left spaces in his Periodic Table so that new elements (then undiscovered) would fit in |
Name two elements that are gases at 20oC | Oxygen, nitrogen, hydrogen,helium, |
Name two elements that are liquids at 20oC | Bromine, mercury |
What does brittle mean? | Substances that shatter when broken. |
Describe two tests you could carry out to find out if a substance is a metal or non metal | Testing electrical conductivity, hit it with a hammer |
Name one use of chlorine. | Kill bacteria in swimming pools, bleach recycled paper. |
What is a compound? | Two or more elements chemically joined together |
What is a molecule? | Two or more atoms joined together |
How can you show the number of atoms in a compound? | By using a chemical formulae |
Complete the word equation: Iron + oxygen | Iron oxide |
Complete the word equation: Magnesium + chlorine | Magnesium chloride |
What is the formula of water? | H2O |
What elements and how many atoms of each element is there in water | 2 hydrogen, 1 oxygen |
Q20 H2SO4 What are the elements in this compound and how many atoms of each? | 2 hydrogen atoms, 1 sulphur atom and 4 oxygen atoms |
What is the symbol for Iron? | Fe |
Describe how to make magnesium oxide | heat magnesium ribbon in a flame. |
Name one metallic that is magnetic | Iron, nickel, cobalt (steel is not an element; it is a mixture!) |
Name the non metal that conducts electricity | Carbon (graphite—pencil lead) |
When solid iodine is heated it changes to a gas—what is this change called? | Sublimation |
What element has the symbol Na? | Sodium |
What are the symbols for silver and gold? | Au = gold; Ag = silver |
Describe the atoms in an element | All the atoms are the same in an element |
Describe the atoms in a mixture | There are two or more different atoms mixed together but not joined |
The columns down in the periodic table are called.. | Groups |
The rows across the periodic table are called... | Periods |
Describe 2 properties of metals. | Conduct heat, conduct electricity,malleable, ductile, shiny, flexible, (most are) solids at room temperature |
Describe 2 properties of non metals. | Heat and electrical insulators, brittle, gases or liquid at room temperature, melt easily. |
Explain why the case of a plug is made of plastic but the pins are made of metal. | Plastic is insulator so you do not get a shock, metal is conductor so you get electricity. |
What is the word equation for making water? | Hydrogen + oxygen —> hydrogen oxide (water) |
When magnesium is burned -what compound is formed and how does the mass change? | Magnesium oxide is formed and the mass increases |
What is the symbol for Calcium in Spanish? | Ca - it is the same whatever language you speak |
What elements and how many of the atoms are in the compound C6H5OH? | 6 Carbon, 6 hydrogen and 1 oxygen |
What does malleable mean? | It can be easily shaped |
How many atoms are in the compound CaCO3? | 1Calcium atom, 1 Carbon atom and 4 Oxygen.atoms |
Which one is the odd one out? Ne, S, He and Ar? | S because it is not a Noble Gas |
How many arms (outer electrons) does boron have? | 3 |
Which one is the odd one out? Sodium, Lithium, Oxygen, Iron? | Oxygen: the only non-metal. |
How many arms (outer electrons) does Sodium and Potassium have? | 1 |
What is the compound formed when you react calcium and chlorine? | Calcium chloride |
What is the 3 elements in Na2SO4? | 2 Sodium, 1 sulphur and 4 oxygen |
What is the formula for magnesium oxide? | MgO |
Describe particles in an element? | Elements are made of only one type of atom. |
What do B- Boron and C- Carbon have to do with each other on the Periodic Table? | They are on the same Period. |
Why is Mercury an unusual metal?? | It is liquid at room temperature, when the other metals are solid |
What is a compound? | 2 elements stuck together |
What is the difference between Potassium and Chlorine? | Potassium is Metal and Chlorine isn’t. |
What is the difference between metallic elements and non-metallic elements | Metals conduct heat and non-metallic don’t. |
How is Carbon-Dioxide made? And what type of particle is it? Explain why. | When carbon burns in the presence of oxygen it will create Carbon-Dioxide in the air, in the form of a gas. It is a compound because it is 2 elements stuck together. |
what r is a chemical that you start with in a chemical reaction? | reactant |
what p is what is made in a chemical reaction? | product |
Why are helium, neon and argon placed in the same group? | they are noble gases and cannot combine with any other elements |
What is the difference between atoms and elements? | an element is a basic substance which can’t be simplified and an atom is the smallest part of an element |
What is the word equation for the combustion (burning) of Magnesium | Magnesium + Oxygen Magnesium Oxide (MgO) |
When you react Na (sodium) and O (oxygen) what compound do you get? | Sodium oxide |
When 2 or more elements join together, what do you create? | A compound |
What is similar between Radon and Xenon? | they are both Noble Gases, they are unreactive. |
What type of element is found on the left hand side of the Periodic table? | Metal |
Explain why Oxygen is a gas | There are weak forces between Oxygen molecules. |
What is the difference between Chlorine and Bromine? | Chlorine is a gas at room temperature and Bromine is a liquid. |
What compound is formed when you add Magnesium and Oxygen together? | it becomes Magnesium Oxide. |
What are 2 common things between Xenon and Chlorine? | they are both gases, they are non-metals. |
How many arms (outer electrons) does Silicon have? | 4 arms |
Explain what happens when Magnesium and Oxygen turns into Magnesium Oxide. | Their arms link together (the Magnesium loses its outer electrons and gives them to the Oxygen) |
What elements are found in Copper Sulfate? | Copper, Sulphur and Oxygen |
Balance the symbolic equation ____ Mg+O2 --> ___ MgO? | 2 Mg+O2 --> 2 MgO? |
What is the difference between Mg and MgO? | MgO is a compound and Mg is and element. |
What compound does Calcium and Oxygen make? | Calcium Oxide |
Compare the particles in mercury and Sodium at room temperature? | mercury’s particles are able to move about as Mercury is liquid, whereas sodium’s particles are organised and tightly linked. |
Explain the difference between a compound and a mixture? | a compound is when you have 2 different elements are joined together. In a mixture, there are 2 different types of particles (2 compounds or 2 different elements or an-element-and-a-compound) BUT the 2 different particles are not joined! |
Can you identify the elements in the compound Na2SO4? | Sodium (2 atoms) sulphur (1 atom) oxygen (4 atoms). |
Can you explain what happens if you mix sulphur with oxygen? What do you get? | The sulphur combines with the oxygen and becomes sulphur dioxide. |
On the periodic table where would you find the non-metals? | on the Right-hand side |
What is a molecule? | two atoms stuck together. |
What do ALL halogens do? | kills bacteria. |
What elements conduct heat? | Metallic elements. |
What is the name of Fe2O3? | Iron Oxide |