Tag: evs

Questions Related to evs

Well developed digestive system is present in

evs more about organ system introduction to excretory system structures and functions related to the excretory system introduction to excretion

  1. Cnidarians, prawns and earthworms

  2. Grasshoppers, frogs and houseflies

  3. Amoeba, Hydra and dog

  4. Sponges, flatworms and earthworms

Show answer
Correct Option: B
Explanation:

Porifera (sponges), Platyhelminthes (flatworms) and Cnidaria (Hydra) do not have a well-developed digestive system. They have 'blind-sac' body plan, with an opening that serves as both the mouth and the anus, and a gastrovascular cavity where digestion takes place.

Earthworms and Arthropods (Grasshoppers, houseflies) have a well-developed digestive system, having a compartmentalized alimentary canal and two-openings, anterior as mouth and posterior as the anus. 
The vertebrates (frogs) also have a well developed digestive system.
Hence, the correct answer is 'Grasshoppers, frogs and houseflies'

When compared to the mammals, birds are less sensitive to temporary deprivation of water, because

evs more about organ system introduction to excretory system structures and functions related to the excretory system introduction to excretion

  1. Urea excretion in mammals entails a greater loss of water than that in birds

  2. Absorption of Water horn the gut is more efficient in birds that in mammals

  3. The water requirement per unit weight is less in birds than in mammal

  4. None of these.

Show answer
Correct Option: A
Explanation:

Birds and reptiles have uric acid as their nitrogenous waste. 

The uricotelic organism excretes uric acid in form of a white paste or powder.
this uric acid is advantaged over the urea which is excreted in mammals in certain ways because it is less toxic and reduces water loss and thus it also reduces the need for water for excretion.

So, the correct option is 'Urea excretion in mammals entails a greater lass of water than that M birds'

Different forms of energies are regarded as non-matter.

evs look, learn and experience matter: states, classification and properties study of matter general introduction: importance and scope of chemistry

  1. True

  2. False

Show answer
Correct Option: A
Explanation:

Any type of energy or an abstract thing is non-matter. Examples are- Sunlight, Gravity, Heat, Reflection, etc.

The element which is a liquid above $30^oC$ is:

evs look, learn and experience matter: states, classification and properties study of matter general introduction: importance and scope of chemistry

  1. Cesium

  2. Lithium

  3. Sodium

  4. Magnesium

Show answer
Correct Option: A
Explanation:

The metals which exists as liquids above 30 degree celcius are :-

1)Mercury-(Also in room temperature) 

2)Cesium

3)gallium

Carbon dioxide is associated with:

evs look, learn and experience matter: states, classification and properties study of matter general introduction: importance and scope of chemistry

  1. Elements

  2. Mixture

  3. Compound

  4. None of these

Show answer
Correct Option: C
Explanation:

Carbon dioxide is a naturally occurring chemical compound composed of 2 oxygen atoms each covalently double bonded to a single carbon atom. It is a gas at standard temperature and pressure and exists in Earth's atmosphere in this state, as a trace gas at a concentration of $0.04 \%$ by volume.

Example of an element is:

evs look, learn and experience matter: states, classification and properties study of matter general introduction: importance and scope of chemistry

  1. Water

  2. Sodium hydroxide

  3. Hydrogen

  4. Sugar

Show answer
Correct Option: C
Explanation:

A chemical element is a pure chemical substance consisting of a single type of atom distinguished by its atomic number, which is the number of protons in its atomic nucleus. If you change the number of protons an atom has, you change the type of element it is.

Here, hydrogen is an element while water, sodium hydroxide and sugar are compounds made up of more than elements.

Classification of matter helps us to:

evs look, learn and experience matter: states, classification and properties study of matter general introduction: importance and scope of chemistry

  1. study things systematically

  2. share information with others

  3. know the properties of all the members of a group if we know about one

  4. All of the above

Show answer
Correct Option: D
Explanation:

Classification of matter helps us to:


(i) Know the properties of all members of a group if we know about one.


(ii) Study things systematically.

(iii) Share information with others.


Option D is correct.

Which among the following is associated with iron sulphide ?

evs look, learn and experience matter: states, classification and properties study of matter general introduction: importance and scope of chemistry

  1. Element

  2. Mixture

  3. Compound

  4. None of these

Show answer
Correct Option: C
Explanation:

Iron(II) sulfide or ferrous sulfide is a chemical compound with the formula $FeS$. Iron sulfides are often non-stoichiometric. powdered iron sulfide is pyrophoric (ignites spontaneously in air).

The property that we use for classifying things depends on the ___________ of the classification.

evs look, learn and experience matter: states, classification and properties study of matter general introduction: importance and scope of chemistry

  1. grouping

  2. purpose

  3. information

  4. system

Show answer
Correct Option: B
Explanation:

Things are always classified to make 

(i)easy identification of things.
(ii)Can know all properties of group if we know about one element in the group.
The property that we use  for classifying things depend on the purpose of classification.

Which of the following is not a transition element?

evs look, learn and experience matter: states, classification and properties study of matter general introduction: importance and scope of chemistry

  1. Mn

  2. Fe

  3. Cu

  4. K

Show answer
Correct Option: D
Explanation:

K belongs to first group. It is a normal metal. Elements of d block are transition metals. Hence K is not a transition metal