Calculations quiz Loading... 1. A sample of bromine contained the two isotopes in the following proportions: bromine-79 = 50.7% and bromine-81 = 49.3%. Calculate the relative atomic mass of bromine(81 + 79)/2 = 80(81x79)/100 = 63.99((81x50.7)+(79x49.3))/100 = 80.01((79x50.7)+(81x49.3))/100 = 79.99Question 1 of 9 Loading... 2. How many protons in a phosphorus atom?16153112Question 2 of 9 Loading... 3. How many electrons in a magnesium atom?13241412Question 3 of 9 Loading... 4. An oxide of nitrogen contains 26% nitrogen and 74% oxygen and has a relative molecular mass of 108. Find the empirical and molecular formulae for the oxide.Empirical formula is N₂O₅. Molecular formula is also N₂O₅Empirical formula is N₂O₅. Molecular formula is N₄O₁₀Empirical formula is N₄O₁₀. Molecular formula is N₂O₅Empirical formula is NO₂.₅ Molecular formula is N₂O₅Question 4 of 9 Loading... 5. State the steps for calculating empirical formula1) Aᵣ/mass. 2) divide by the smallest. 3) Give the ratio has a whole number. 4) State final empirial formula1) mass/Aᵣ. 2) divide by the largest. 3) Give the ratio has a whole number. 4) State final empirial formula1) mass/Ar. 2) divide by the smallest. 3) Give the ratio has a whole number. 4) State final empirial formula1) Aᵣ/mass. 2) divide by the largest. 3) Give the ratio has a whole number. 4) State final empirial formulaQuestion 5 of 9 Loading... 6. What is meant by the term molecular formula?A chemical formula that shows the actual numbers of the different types of atoms in a moleculeA chemical formula that shows the simplest ratio of the numbers of atoms in a compoundA method of calculating the ratios of masses in an equationA method of calculating the mass needed to make a certain yield in an equationQuestion 6 of 9 Loading... 7. To determine the formula of a metal oxide by combustion, magnesium is heated in a crucible. Why is the crucible is cooled, weighed, reheated, cooled, re-weighed, and so on?To make sure the mass is still going down so the magnesium is still reactingTo make sure a constant mass has been reached and there is no more magnesium left to reactTo ensure all the magnesium oxide to escapeTo allow any water to escapeQuestion 7 of 9 Loading... 8. Calculate the relative formula mass(Mr) of propane (C₃H₈)44472652Question 8 of 9 Loading... 9. What are the three subatomic particles?protons, neutrons and electronsAtoms, molecules and ions+1, 0 and -1Chlorine, bromine, iodineQuestion 9 of 9 Loading... Related Posts:The entire quiz question bank!The entire quiz question bank (Double only)!Key Calculations quizEquilibria (triple) quizCondensation Polymers quizElectrolysis quiz Hydr0Gen2020-02-16T16:38:53+00:00Categories: Uncategorized|Tags: Quiz, Topic: Calculations| Share This Story, Choose Your Platform! FacebookTwitterRedditLinkedInTumblrPinterestVkEmail