Topic 5a Mass calculations, electrolysis, extraction of metals and equilibria Flashcards Preview

Edexcel GCSE Combined Science (Chemistry) HIGHER > Topic 5a Mass calculations, electrolysis, extraction of metals and equilibria > Flashcards

Flashcards in Topic 5a Mass calculations, electrolysis, extraction of metals and equilibria Deck (110)
Loading flashcards...
1

1. What is the formula of water?

H2O

2

2. What is the formula of sodium chloride?

NaCl

3

3. What is the formula of carbon dioxide?

CO2

4

4. The formula of magnesium chloride is MgCl2. What is the ratio of magnesium ions to chloride ions?

1:2

5

5. The formula of sulfuric acid is H2SO4. How many atoms of each element are in the formula?

H = 2, S = 1, O = 4

6

6. The formula of calcium nitrate is Ca(NO3)2. How many calcium, nitrogen and oxygen atoms are in the formula?

Ca = 1, N = 2, O = 6

7

7. There are two numbers alongside chlorine in the periodic table, 17 and 35.5. What does the number 17 represent?

atomic number

8

8. What does the number 35.5 represent?

relative atomic mass

9

9. Sodium chloride has the formula NaCl. The relative atomic mass of sodium is 23 and that of chlorine is 35.5. What is the relative formula mass of NaCl?

58.5

10

10. A water molecule has the formula H2O. The relative atomic mass of hydrogen is 1 and that of oxygen is 16. What is the relative formula mass of a molecule of water?

18

11

11. What is the symbol for relative atomic mass?

Ar or RAM

12

12. What is the symbol for relative formula mass?

Mr or RFM

13

13. The relative atomic mass of hydrogen is 1. What is the relative formula mass of hydrogen molecules?

2

14

14. Sodium chloride has the formula NaCl; the relative atomic mass of sodium is 23 and that of chlorine is 35.5. What is the relative formula mass of NaCl?

58.5

15

15. A water molecule has the formula H2O; the relative atomic mass of hydrogen is 1 and that of oxygen is 16. What is the relative formula mass of water?

18

16

16. A carbon dioxide molecule has the formula CO2; the relative atomic mass of carbon is 12 and that of oxygen is 16. What is the relative formula mass of carbon dioxide?

44

17

17. What is the empirical formula of a compound with molecular formula C2H4?

CH2

18

18. What is the empirical formula of a compound with molecular formula C3H8?

C3H8

19

19. A sample of magnesium carbonate was heated in an open test tube. Why did it lose mass?

gas/carbon dioxide escaped

20

20. 100 cm3 of a solution contained 2 g of salt. What is the concentration of the salt in g dm-3?

20

21

21. A sample of copper carbonate was heated in an open test tube. Why did it lose mass?

gas/carbon dioxide escaped

22

22. Why does magnesium increase in mass when it is heated in air?

combines with oxygen

23

23. How many cm3 are there in 1 dm3?

1000

24

24. What is 250 cm3 expressed in dm3?

0.25

25

25. What is 0.5 dm3 expressed in cm3?

500

26

26. 100 cm3 of a solution contains 1.5 g of salt. What is the concentration of the salt solution in g dm3?

15

27

27. 250 cm3 of a solution contains 5 g of sugar. What is the concentration of the sugar solution in g dm3?

20

28

28. A solution of copper sulfate has concentration 10 g dm3. What mass of copper sulfate will be dissolved in 100 cm3 of solution?

1 g

29

29. 2 g of hydrogen reacts with oxygen to form 18 g of water. What mass of water will be formed from 1 g of hydrogen?

9 g

30

30. 2H2 + O2 →  2H2O. How many molecules of hydrogen are needed to react with 1 dozen molecules of oxygen to form water?

2 dozen