Advertisements
Advertisements
Question
A sample of vitamic C is known to contain 2.58 ×1024 oxygen atoms. How many moles of oxygen atoms are present in the sample?
Advertisements
Solution
Number of oxygen atoms in the sample = 2.58 x 1024
= 2.58 × 1024
6.022 × 1023 atoms of oxygen = 1 mole
2.58 × 1024 atoms of oxygen = `(2.58 xx 10^24)/(6.022 xx 10^23)` moles
= 4.28 moles
APPEARS IN
RELATED QUESTIONS
Why is it not possible to see an atom with naked eyes?
If bromine atom is available in the form of, say, two isotopes `""_35^79Br (49.7%)" and """_35^81Br (50.3%)`, calculate the average atomic mass of bromine atom.
TRUE \ FALSE
Cathode rays are a stream of fast moving particles that travel in random directions.
State Dalton’s atomic theory.
A certain particle ‘X’ has 17 protons, 18 electrons and 20 neutrons.
What is such a particle called ?
Fill in the blank
If an atom gains an electron, it is called an _______
Fill in the blank
An excess of electrons produces a ________ charge.
What value has been given to the mass of this reference atom ?
The electronic configuration of an element Z is 2, 8, 8.
(a) What is the atomic number of the element?
(b) State whether element Z is a metal or a non-metal.
(c) What type of ion (if any) will be formed by an atom of element Z? Why?
(d) What is special about the outermost electron shell of the atom of this element?
(e) Give the name and symbol of element Z.
(f) Name the group of elements to which Z belongs.
How many atoms are there in exactly 12 g of carbon-12 element ? (C = 12 u)
Calculate the number of moles in 12.044 × 1025 atoms of phosphorus.
State the meaning of the term – (a) atom, (b) molecule, (c) radical – with a suitable example.
A radical take part – unsplit in a chemical reaction and retains its identity in reactions.
With reference to the radical –
- ammonium
- bisulphate
- carbonate
state the group of atoms present in each radical.
An atom of an element has no electron. Will that atom have any mass or not? Can an atom exist without electron? If so then give example.
Define the following term with an example.
Non-metal
Which of the following statements made by Dalton has not undergone any change?
The smallest unit of an element is ______.
______ is a substance that is made up of three oxygen atoms chemically combined.
