Question

A black dot used as a full stop at the end of a sentence has a mass of about one attogram. Assuming that the dot is made up of carbon, calculate the approximate number of carbon atoms presents in the dot?  

Solution

Correct option is

 

ass of c carbon in the atom =1 attogram = 10–18 g

Gram atomic mass of carbon = 12 g

i.e., 12 g of carbon contain  atoms of carbon

 

 

SIMILAR QUESTIONS

Q1

10 litres of O2 gas is reacted with 30 litres of CO at STP. The volume of each gas present at the end of the reaction are

Q2

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Q3

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Q4

What volume of oxygen gas (O2) measured at 0oC and 1 atm is needed to burn completely 1 L of propane gas (C3H8messured under the same conditions?

Q5

An organic compound contains carbon, hydrogen and oxygen. Its chemical analysis gave C, 38.71 % and H, 9.67%. The empirical formula of the compound would be  

Q6

How many moles of lead (II)chloride will be formed from a reaction between 6.5 g of PbO and 3.2 g of HCl

Q7

0.1 mole of a carbohydrate with empirical formula CH2O contains 1 g of hydrogen. What is its molecular formula? 

Q8

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Q9

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Q10

Insulin contains 3.4% sulphur. Calculate the minimum molecular mass of insulin.