Science (English Medium) इयत्ता ११ - CBSE Question Bank Solutions for Chemistry

From where does ozone come in the photochemical smog?

Assertion (A): Photochemical smog is oxidising in nature.

Reason (R): Photochemical smog contains NO₂ and O₃, which are formed during the sequence of reactions.

How can you apply green chemistry for the following:

To control photochemical smog.

Match the following prefixes with their multiples:-

Convert the following into basic units:

28.7 pm

Convert the following into basic units:

15.15 pm

Convert the following into basic units:

25365 mg

In terms of period and group, where would you locate the element with Z =114?

Which element do you think would have been named by Lawrence Berkeley Laboratory?

Which element do you think would have been named by Seaborg’s group?

Find:

1. the total number and 
2. the total mass of neutrons in 7 mg of ¹⁴C.

(Assume that mass of a neutron = 1.675 × 10⁻²⁷ kg).

Find (a) the total number and (b) the total mass of protons in 34 mg of NH₃ at STP. Will the answer change if the temperature and pressure are changed?

How many neutrons and protons are there in the following nuclei?

`""_6^13"C"`, `""_8^16"O"`, `""_12^24"Mg"`, `""_26^56"Fe"`, `""_38^88"Sr"`

An atom of an element contains 29 electrons and 35 neutrons. Deduce (i) the number of protons and (ii) the electronic configuration of the element.

Write Lewis dot symbols for atoms of the following elements: Mg, Na, B, O, N, Br.

Draw the Lewis structures for the following molecule and ion:

H₂S

Draw the Lewis structures for the given molecule and ion:

SiCl₄

Draw the Lewis structures for the given molecule and ion:

BeF₂

Draw the Lewis structures for the given molecule and ion:

`"CO"_3^(2-)`

Draw the Lewis structures for the following molecule and ion:

HCOOH