What Causes Difficulty in Understanding Chemistry?

[gotzmlk]

Hi, I am having a huge problem with chem. i do not know what the heck is going on so can i have some help.




Drops of each chemical into test tubes
=====================================================================
ratios Ca:CO
test tube1: 0:24
test tube2: 1:5
test tube3: 1:2
test tube4: 1:1
test tube5: 2:1
test tube6: 5:1
test tube7: 24:0
=====================================================================

Determining Chemical Formulas I
11. Based on valence, what do you think is the correct chemical formula for calcium carbonate?
CaCO3

12. Do your experimental results for the chemical formula for calcium carbonate agree with your chemical formula in question #11?


13. What is the name of the new solid formed in the reaction?
Salt

14. What is the name of the new liquid formed in the reaction?


15. Write the name of each of the compounds below the chemical equation, which shows what reaction, took place:

CaCl2 + Na2CO3 à 2 NaCl

_____________ _________________ __________________


_____________ _________________ __________________

16. If the correct formula for calcium carbonate had been Ca2CO3, which test tube would have contained the greatest amount of precipitate?

17. If the correct formula for calcium carbonate had been Ca(CO3)5, which test tube would have contained the greats amount of precipitate?

18. If the correct formula for calcium carbonate had been Ca(CO3)2, which test tube would have contained the greats amount of precipitate?

19. How could you experimentally determine the correct chemical formula for the new liquid formed?

20. How were the rations of calcium and carbonate determined?


Drops of each chemical into test tubes
=====================================================================
ratios: Cu:OH
test tube1: O:24
test tube2: 1:5
test tube3: 1:2
test tube4: 1:1
test tube5: 2:1
test tube6: 5:1
test tube 7: 24:0
=====================================================================

Determining Chemical Formulas II
1. List the elements and the number of atoms of each element in one molecule of copper sulfate?

2. How many different elements are in one molecule of copper sulfate?


3. How many total atoms are in one molecule of copper sulfate

4. What is the symbol and valence for copper II?


5. What is the formula and valence for sulfate?

6. List the elements and the number of atoms of each element in one molecule of sodium hydroxide?


7. How many different elements are in one molecule of sodium hydroxide?

8. How many total atoms are in once molecule of sodium hydroxide?


9. What is the symbol and valence for sodium?

10. What is the formula and valence for hydroxide?


11. Based in valence, what do you think is the correct chemical formula for copper hydroxide?

12. Do your experimental results for the chemical formula for copper hydroxide agree with your chemical formula in question #11?


13. What is the name of the new solid formed in the reaction?

14. What is the name of the new liquid formed in the reaction?


15. Write the name of each of the compounds below the chemical equation, which shows what reaction, took place:

CuCO4 + 2 NaOH à Na2SO4

_____________ _________________ __________________


_____________ _________________ __________________

16. If the correct formulae for calcium carbonate had been CuOH, which test tube would have contained the greats amount of precipitate?

17. If the correct formulae for calcium carbonate had been Cu2OH, which test tube would have contained the greats amount of precipitate?


18. If the correct formulae for calcium carbonate had been Cu(OH)5, which test tube would have contained the greats amount of precipitate?

19. How could you experimentally determine the chemical formula for the new liquid formed?

 

[agnostictheist]

what I can remember

please note, while my degree was in chemistry, its been a while and I am very likely to get them wrong!... will answer form what think I KNOW!

. How many total atoms are in one molecule of copper sulfate

CuSO 4

6

What is the formula and valence for hydroxide?

-OH

its - 1

What is the formula and valence for sulfate?

- 2 I THINK!

S04

What is the symbol and valence for sodium?

Na

Na is plus one Na +1

List the elements and the number of atoms of each element in one molecule of sodium hydroxide?

Na only one
O only one
H only one

thus full forumla

NaOH

How could you experimentally determine the chemical formula for the new liquid formed?


tell me the product please?

most (carbon cont) chemicals can be tested using some forms of spectroscopy!

sorry don't have enough time...