MATHS ( SIG FIG ) AND ALSO CHEM QUESTION PART 2 .. PLEASE HELP

[matt123]

okkk guys
so i got a few questions from the book that im stuck on ..

first one is a maths one

14.00/37.800 X 6.022 = TO THE right amount of sig figs !!
the options are

2.23037
2.23
2.2
2.230
2.2304

i think its 2.230

can some 1 please help me?

2 also
chem questions

aluminium ion al3+ has ..
i said ... 13 protons and 10 electrons .. is this correct?

also 3
gadolinium oxide contains 86.76 mass % GD. .. determine its empirical forumla ... i said Gd203... is this correct ?



also 4 is the correct name for N203 = dinitrogen trioxide?

also 5
 
which of the following is most likely to form when an S atom forms an ion
S6+
S2-
S4+
S4-
none of the above
and i said ... S2- .. is this correct?


please help me !!

many many thanks in advanced guys.

[jane1234]

14.00/37.800 X 6.022 = TO THE right amount of sig figs !!
the options are

2.23037
2.23
2.2
2.230
2.2304

i think its 2.230

can some 1 please help me?

Think you're right ... generally it is the least number of sig figures given in the question...

[matt123]

hmmm ok i hope so

some one pleasseee help me with the rest!
ahah

[pi]

also 5
 
which of the following is most likely to form when an S atom forms an ion
S6+
S2-
S4+
S4-
none of the above
and i said ... S2- .. is this correct?

Correct, sulfide ions are S^2-

2 also
chem questions

aluminium ion al3+ has ..
i said ... 13 protons and 10 electrons .. is this correct?

Correct

also 4 is the correct name for N203 = dinitrogen trioxide?

Correct

also 3
gadolinium oxide contains 86.76 mass % GD. .. determine its empirical forumla ... i said Gd203... is this correct ?

Correct