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Calculations
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Joined: 09/04/2014 - 15:52
Posts: 1
Calculations

Hi!! I really need help for calculations. I'm not understanding a thing!!!!!!!!

chiedza22
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Joined: 12/04/2014 - 11:33
Posts: 1
calculations

i also need so much help. cant do anything with moles!!!

LauraMounsey
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Joined: 04/05/2014 - 14:23
Posts: 3
Hi,

Hi,

1 mole  is it's relative atomic mass in grams

To work out how many moles are of an element, use the formula;

no of moles= mass(g) divided by R.A.M

For example, "How many moles of sodium are there in 2.3g?"

2.3/23=0.1 so there are 0.1 moles.

Hope this helped, but im a bit rubbish at explaining thingss :P Good Luck!

LauraMounsey
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Joined: 04/05/2014 - 14:23
Posts: 3
Hi,

Hi,

1 mole  is it's relative atomic mass in grams

To work out how many moles are of an element, use the formula;

no of moles= mass(g) divided by R.A.M

For example, "How many moles of sodium are there in 2.3g?"

2.3/23=0.1 so there are 0.1 moles.

Hope this helped, but im a bit rubbish at explaining thingss :P Good Luck!

LauraMounsey
Offline
Joined: 04/05/2014 - 14:23
Posts: 3
Hi,

Hi,

1 mole  is it's relative atomic mass in grams

To work out how many moles are of an element, use the formula;

no of moles= mass(g) divided by R.A.M

For example, "How many moles of sodium are there in 2.3g?"

2.3/23=0.1 so there are 0.1 moles.

Hope this helped, but im a bit rubbish at explaining thingss :P Good Luck!

Inez Lynn Matic
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Joined: 09/05/2014 - 15:31
Posts: 1

helo.i saw your post and think i can be of help to you

Online Communit...
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Joined: 28/01/2014 - 14:18
Posts: 630
You could try this section of
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Joined: 18/09/2014 - 12:29
Posts: 1
ACCELERATION DUE TO GRAVITY

A ball is dropped from the leaning tower of Pisa, at a height of 50m from the ground. The ball is dropped from rest and falls freely under gravity. How long will it be before the ball hits the ground?

We know: s = 50, a = 9.8, u = 0 and we want to find t.

The equation connecting these four is s = ut + ½ at2

So 50 = 0 + ½ × 9.8 × t2
Rearranging: t2 = 10.20408
t = 3.19…
the time taken is 3.19s (3sf)

CAN SOMEONE ASSIST ME BY EXPLAINING HOW THEY GOT THE 3.19 BECAUSE TO MY UNDERSTANDING I UNDERSTAND THAT YOU HAVE TO RE ARRANGE THE FORMULA AND MAKE "T" THE SUBJECT OF THE FORMULA BECAUSE THATS WHAT WE WERE ASKED TO FIND

dr.ijrudolph
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Joined: 14/01/2015 - 10:54
Posts: 1
calculations

which calculations? molar? redox? thermo?