Question

i) Define atomic mass unit.

ii) What is the numerical value of mole.

iii) Name the elements present in oxide ion

paper question of 9th class annual exam cbse
JNV AKOLA​

Answer 1

${ \huge{ \mathfrak{ \underline{ \underline{ \pink{Aꪀsᴡꫀr}}}}}}$

Hᴇʀᴇ ɪs ᴜʀ Aɴsᴡᴇʀ

ǫᴜᴇsᴛɪᴏɴ :-

☆ Define atomic mass unit.

☆ What is the numerical value of mole.

☆ Name the elements present in oxide ion

----------------------------------------------

ᴀɴsᴡᴇʀ :-

1 . ☆ A unit of mass used to express atomic and molecular weights, equal to one twelfth of the mass of an atom of carbon-12.

☆ An atomic mass unit is defined as a mass equal to one twelfth the mass of an atom of carbon-12. The mass of any isotope of any element is expressed in relation to the carbon-12 standard. For example, one atom of helium-4 has a mass of 4.0026 amu.

----------------------------------------------

2 .☆ One mole contains exactly 6.022 140 76 x 1023 elementary entities. This number is the fixed numerical value of the Avogadro constant, NA, when expressed in the unit mol–1 and is called the Avogadro number.

----------------------------------------------

3 .☆ An oxide (/ˈɒksaɪd/) is a chemical compound that contains at least one oxygen atom and one other element in its chemical formula. "Oxide" itself is the dianion of oxygen, an O2– (molecular) ion. Metal oxides thus typically contain an anion of oxygen in the oxidation state of −2.

----------------------------------------------

BᴇʀʀʏCʀᴜsʜ ❤︎

Answer 2

Answer:

I. refer the above attachment

ii Avogadro constant

iii oxygen