Explore topic-wise InterviewSolutions in Current Affairs.

List some of the applications for which a screw gauge can be used.

Magnesium ribbon burns in air to produce which type of reaction?

Which of the following gases when dissolved in aqueous solution of SO₂ give sulphuric acid as a product?

What is meant galvanisation? Why is it done?

(a) What is a food chain? Give one example of a simple food chain.

(b) What is a 'food web'? Show its formation.

Question 2.28

Calculate the mass percentage of aspirin $\left(C_9{H}_8{O}_4\right)$ in acetonitrile $\left(C{H}_{3}CN\right)$ when 6.5g of $C_9{H}_8{O}_4$ is dissolved in 450 g of $C{H}_{3}CN$

Which of the following is(are) burnt for producing SO₂ in the first step of the industrial preparation of sulphuric acid?

Question 64
An element A burns with golden flame in air. It reacts with another element B, atomic number 17 to give a product C. An aqueous solution of product C on electrolysis gives a compound D and liberates hydrogen. Identify A, B, C and D. Also write down the equations for the reactions involved.

Equal volumes of ethene and hydrogen at same temperature and pressure are passed through catalyst maintained at 300⁰C, an addition reaction takes place. The catalyst used is:

What is the difference between diluted acid and concentrated acid

$Mg+RI\to$ ________

What are chlorofluorocarbons? Why are they considered as air pollutants?

The given sample of hydrochloric acid contains only 20% by weight of HCl, the rest being water.What mass of the acid will be required for reacting completely with 20 g of magnesium oxide?

Classify salts and explain each of them with examples.

From the part of a periodic table, answer the following question:
$\begin{array}{ccccccc}1& 2& 13& 14& 15& 16& 17\\ Hydrogen& & & Carbon& & Oxygen& Fluorine\\ X& & & P& & & Q\\ Y& & & & & & R\\ Z& & & & & & T\end{array}$
Out of 'X' and 'Q' which element has larger atomic size?

Choose the correct statements regarding corrosion from the options given below.

There were two metals, Metal A and B. Both were extracted by means of electrolytic reduction of their molten salts. Metal A and B are:

Which of the following componds are not formed during electrolysis?

The solubility product of $Ca(OH{)}_{2}at{25}^{\circ }Cis4.42\times {10}^{-5}$. A 500 ml of saturated solution of $Ca(OH{)}_2$ is mixed with equal volume of 0.4M NaOH solution. How much $Ca(OH{)}_2$ in milligrams is precipitated

Atomic mass of X and Z are 20 and 40 respectively. If X, Y and Z are in Dobereiner’s triads, what should be the atomic mass of Y?

Which of the following types of medicine is used for treating indigestion caused by over-eating ?

(a) antibiotic

(b) analgesic

(c) antacid

(d) antiseptic

(a) Explain why a food chain usually cannot have more than three or four steps.

(b) Calculate the amount of energy that will be available to big fish in the following food chain, if 10,000 J of energy is available to small algae from the sun :

$Smallalgae\to Zooplankton\to Fish\to Bigfish$

The product obtained when Iron reacts with dilute sulphuric acid is :

Which one of the following is the most electropositive element?

On 1st October, 2012 a truck was purchased for Rs. 8,00,000 by Laxmi Transport Ltd. Depreciation was provided at 15 % per annum on the diminishing balance basis on this truck. On 31st December, 2016 this truck was sold for Rs. 5,00,000. Accounts are closed on 31st March, every year. Prepare a truck account for the 4 years.

When methane is combusted, products formed are___ .

What is the mass of $80c{m}^3$ of carbon dioxide at S.T.P

Observe the modern periodic table and explain the graduation in reactivity of halogen family

Which of the following will be able to show geometrical isomerism?

How we can find that a salt formed by neutralisation reaction is an acidic salt or basic salt

What is flora?

Question 39
On heating blue-colored powder of copper (II) nitrate in a boiling tube, copper oxide (black), oxygen gas, and a brown gas X are formed

(a) Write a balanced chemical equation of the reaction.
(b) Identity the brown gas X evolved.
(c) Identity the type of reaction.
(d) What could be the pH range of the aqueous solution of the gas X?

The nature of the precipitate formed when sodium hydroxide reacts with iron (II) sulphate is of

The reaction: takes place in the gaseous state. If all volumes are measured at the same temperature and pressure,

Calculate the volume of dinitrogen oxide (N₂O) required to give 150 cm³ of steam.

[N = 14,O = 16,C=12,H=1]

Ordinary chlorine has two isotopes${}_{17}^{35}Cl$ and${}_{17}^{37}Cl$ in the ration of 3:1 Calculate the relative atomic mass of chlorine.

Which of the following sewage disposal system is used in hospitals?

IUPAC name of CH₃COOH is:

The energy required to remove an electron of a gaseous atom from its ground state is called

Two gases are released when conc. sulphuric acid reacts with :

How to solve a chemical equations and how to balanced a chemical equation with some examples.Step by step.In each step with some hard equations????? Please

(i) Comprehension given below is followed by some multiple choice questions. Each question has one correct option. Choose the correct option. In the modern periodic table, elements are arranged in order of increasing atomic numbers which is related to the electronic configuration. Depending upon the type of orbitals receiving the last electron, the elements in the periodic table have been divided into four blocks, viz s, p, d, and f.
The modern periodic table consists of 7 periods and 18 groups. Each period begins with the filling of a new energy shell. In accordance with the Aufbau principle, the seven periods (1 to 7 ) have 2, 8, 8, 18, 18, 32, and 32 elements respectively.
The seventh period is still incomplete. To avoid the periodic table being too long , the two series of f-block elements, called lanthanoids and actionoids are placed at the bottom of the main body of hte periodic table
The element with atomic number 57 belongs to
(a) s- block ( b) p-block (c) d- block (d) f- block

(ii) The last element of the p - block in 6th period is represented by the outermost electronic configuration.
(a) $7s^{2}7p^6$ (b) $5f^{14}6d^{10}7s^{2}7p^0$
(c) $4f^{14}5d^{10}6s^{2}6p^6$ (d) $4f^{14}5d^{10}6s^{2}6p^4$

(iii) Which of the elements whose atomic numbers are given below, cannot be accommodated in the present set up of the long frm of the periodic table?
(a) 107 (b) 118 (c) 126 (d) 102

(iv) The electronic configuration of the element which is just above the element with atomic number 43 in the same group is .....
(a) $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{5}4s^2$
(b) $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{5}4s^{3}4p^6$
(c) $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{6}4s^2$
(d) $1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{7}4s^2$

(v) The elements with atomic numbers 35, 53 and 85 are all ..
(a) noble gases (b) halogens (c) heavy metals (d) light metals

When $0.44g$ of a colourless oxide of nitrogen occupies $224mL$ at $1520mm$ of $Hg$ and \(273^{\circ}C\) , then the oxide is

The metal M reacts vigorously with water to form a solution S and a gas G. The solution S turns red litmus to blue whereas gas G, Whcih is lighter than air, burns with a pop sound. Metal M has a low melting point and it is used as a coolant in nuclear reactors.

(a) What is metal M ?

(b) What is solution S ? Is it acidic or alkaline ?

(c) What is gas G ?

(d) Write a balanced chemical equation for the reaction which takes when metal M reacts with water.

(e) Is this reaction exothermic or endothermic ?