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chemistry
| Question | Answer |
|---|---|
| What is the relative atomic mass of an electron? | 1/2000 |
| What isotope is used as the standard against which massas are measured? | Carbon-12 |
| What is the relative formular mass of CO2 | 44 |
| There a 4 moles of potassium oxide, what is the mass of the compound? | 376.8g |
| There is 48000cm of carbon monoxide in the room. how many moles is this | 2 |
| balance: HNO3+MgO=Mg(NO3)2+H2O | 2HNO3+MgO>Mg(NO3)2+H2O |
| a litre of HCl with a concentration of 25 moles/dm concentrations. how many moles is there? | 25 moles |
| It takes 25dm of a acid to neutralise 30dm of an alkali with a concentration of 2moles/dm how many moles is the acid when the formula has equal number of each compound? (NaOH+HCl) | 60 moles |
| Define Acid | A species that is a proton (H+ ion) donor |
| H2SO4+aq= | 2H++SO4- |
| Define Base | Aspecies that is a proton (H+ ion) acceptor |
| Define Alkali | A type of base that dissolves in water to form (OH-) ions |
| What is the Oxidation no. of combined oxygens? | -2 |
| What has been done to an element if the oxidition number becomes more positive? | It has been oxidised |
| What has been done to an element when the oxidation number becomes more negative? | It has been reduced |
| What does the roman numerals stand for in Iron (III)? | Its oxidation number is +3 |
| In a half equation Magnesium becomes what? | Mg2+ and 2e- |
| What has been oxidised in this equation, Hcl+NaOH=NaCl+H2O | Cl |
| how many electrons does O have? | 8 |
| How many electrons does O1- have? | 9 |
| What sub shell is the outer electrons of Oxygen in? | 2 P-block |
| What two types elements join in an ionic bond? | Metal and Non-metal |
| What is the charge on a carbonate ion? | 2- |
| What two types of elements join in a covalent bond? | Non-metal and Non-metal |
| What is the angle size of NH3? | 107 degrees |
| Going down the period what happens to the electronegativity? | increases |
| Describe a metallic bond? | A large amount of positive ions in a "sea of delocalised electrons" |