C5- Part 1 0.0 / 5 ? ChemistryAtomsAtoms and compoundsAcids, bases and saltsAnalysing substancesGCSEOCR Created by: bwyatt36Created on: 06-05-16 12:58 Name the parts of an atom and their charges. Nucleus- neutral Proton- positive Electrons-negative 1 of 9 What two different bonds are their between atoms and what is the difference between them? Ionic bond- When a positive and negative ion attract and join together. Covalent- This is where atoms share a pair of electrons. 2 of 9 Balance this equation: H2SO4 + NaOH > Na2SO4 + H2O H2SO4 + 2NaOH > Na2SO4 + 2H2O 3 of 9 Atoms and molecules masses are compared to 1/12th the mass of an atom of which isotope of carbon? Carbon-12 4 of 9 How many moles are there in 284g of sodium sulfate, Na2 SO4? Mr = (23x2) + 32 + (16x4) = 142 moles =mass/Mr 284/142 = 2moles 5 of 9 What are empirical formulas ? Empirical formulas are the simplest ratio of atoms in a compound. 6 of 9 The concentration of a solution is measured in what ? moles per dm^3 7 of 9 How do you calculate the number of moles? Number of moles = mass/relative formula mass 8 of 9 If a slice of bread has 0.2g of sodium how much salt does it contain? Ar sodium = 23 and Mr sodium chloride = 58.5 Find the ratio between the Mr and Ar: 58.5/23 = 2.543... Multiply by the amount of sodium: = 0.5086 = 0.5g of salt 9 of 9
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