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What is petrolium

Posted by Sahil Patel 3 years, 5 months ago

CBSE > Class 08 > Science

2 answers

Harshita Dogra 3 years, 4 months ago

Spelling - PETROLEUM

Pranav Prabhakar 3 years, 5 months ago

mineral oil that is found under the ground or sea and is used to make petrol, plastic and other types of chemical substances is called petroleum.

ANSWER

The sting of an ant contains___________. a) hydrochloric acid b) formic acid c) sulphuric acid d) nitric acid

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

5 answers

Lanin Gogoi 3 years, 5 months ago

Formic acid

Soumya Subhankar Sahoo 3 years, 5 months ago

(b) Formic Acid

Subrat Kumar Panda 3 years, 5 months ago

Answer is b

Subrat Kumar Panda 3 years, 5 months ago

What a easy questions you send

Stuti Tripathi 3 years, 5 months ago

B is the correct answer

ANSWER

Phenolphthalein is a synthetic indicator and its colour in acidic and basic solutions, are a) red and blue b) blue and red c) pink and colourless d) colourless and pink

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

3 answers

Pranav Prabhakar 3 years, 5 months ago

b)blue and red

Lanin Gogoi 3 years, 5 months ago

Maybe d

Soumya Subhankar Sahoo 3 years, 5 months ago

Maybe C

ANSWER

Products of a neutralization reaction are always: a) an acid and a base b) an acid and a salt c) a salt and water d) a salt and a base

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

2 answers

Pranav Prabhakar 3 years, 5 months ago

c)a salt and water

Kanu Choudhary 3 years, 5 months ago

Acid and base

ANSWER

To protect tooth decay, we are advised to brush our teeth regularly. The nature of the tooth paste commonly used is: (a) acidic (b) basic (c) neutral (d) corrosive

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Priyanshi Mittal 3 years, 5 months ago

Basis

ANSWER

The substance whose odour changes in acidic (or) basic solutions are called a) universal indicators b) olfactory indicators c) natural indicators d) mixed indicator

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

The chemical name of washing soda is a) sodium bicarbonate b) sodium carbonate c) sodium hydroxide d) sodium chloride

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Priyanshi Mittal 3 years, 5 months ago

Sodium carbonate

ANSWER

Which nature does pH=7 solutions have? a) acidic b) basic c) neutral d) amphoteric

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Dinesh Choudhary 3 years, 5 months ago

Answer is c

ANSWER

Bases which are soluble in water are called a) acids b) alkaloids c) aromatics d) alkalis

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

pH scale was proposed by a) Sorensen b) Bohr c) Maxwell d) Schrodinger

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Dinesh Choudhary 3 years, 5 months ago

Answer is a

ANSWER

What is the colour of methyl orange in acidic medium a) red b) pink c) colourless d) yellow

Posted by Hirenya A 3 years, 3 months ago

CBSE > Class 08 > Science

1 answers

Sia ? 3 years, 3 months ago

red

ANSWER

Acids, Bases and Salts The acid which is completely ionized into its ions is called as a) weak acid b) strong acid c) acidic salt d) none of these

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

14 Which amongst the following symbols is the correct representation for the formation of a precipitate? a) b) ↑ c) ↓ d) 

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

The colour of iron sulphate (aqueous) is a)Green b) Colourless c) Blue d) Pink 14 Which amongst the following symbols is the corr

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

Which one of the following processes involves chemical reactions? a) Storing of oxygen gas under pressure in a gas cylinder b) Liquefaction of air c) Keeping petrol in a china dish in the open d) Heating copper wire in presence of air at high temperature

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

The following reaction is used for the preparation of oxygen gas in the laboratory 2Kclo3(s) →2Kcl(s) +3o2 (g) Which of the following statement(s) is(are) correct about the reaction? a) It is a decomposition reaction and endothermic in nature b) It is a combination reaction c) It is a decomposition reaction and accompanied by release of heat d) It is a photochemical decomposition reaction and exothermic in nature

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

Which of the following gases can be used for storage of fresh sample of oil for a long time? a) Carbon dioxide or oxygen b) Nitrogen or oxygen c) Carbon dioxide or helium d) Helium or nitrogen

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

In double displacement reaction between aqueous potassium iodide and aqueous lead nitrate, a yellow precipitate of lead iodide is formed. While performing the activity if lead nitrate is not there, which of the following can be used in place of lead nitrate? a)Lead sulphate (insoluble) b) Lead acetate c) Ammonium nitrate d) Potassium sulphate

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

Which of the following is(are) an endothermic process(es)? a) Dilution of sulphuric acid b) Sublimation of dry ice c) Condensation of water vapours d) Evaporation of water a) A and C b) B only 3) C only 4) B and D

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

Electrolysis of water is a decomposition reaction. The mole ratio of hydrogen and oxygen gases liberated during electrolysis of water is a) 1:1 b) 2:1 c) 4:1 d) 1:2

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

Barium chloride on reacting with ammonium sulphate forms barium sulphate and ammonium chloride. Which of the following represent the type of the reaction involved? a) Displacement reaction b) Precipitation reaction c) Combination reaction d) Double displacement a) A only b) B only 3) D only 4) B and D

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

Which among the following is (are) double displacement reaction(s)? a) Pb + CuCl2 → PbCl2 + Cu b) BaCl2 + Na2 SO4 → BaSO4 + 2NaCl c) C + O2 → CO2 d) CH4 + 2O2 → CO2 + 2H2 O a) A and D b) B only c) A and B d) C and D

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

A dilute ferrous sulphate solution was gradually added to the beaker containing acidified permanganate solution. Light purple colour of the solution fades and finally disappears. Which of the following is the correct explanation for the observation? a.KMno4 is an oxidising agent, it oxidises FeSO4 b. FeSO4 acts as an oxidising agent and oxidises KMno4 c. The colour disappears due to dilution, no reaction involved. d.KMno4 is an unstable compound and decomposes in presence of FeSO4 to a colourless compound

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

Which of the following are exothermic processes? a) Reaction of water with quick lime b) Dilution of an acid c) Evaporation of water d) Sublimation of camphor (crystals)

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

The following reaction is an example of a 4NH3(g) + 5O2(g) → 4NO (g) + 6H2O(g) a)Displacement reaction b) Combination reaction c) Redox reaction d) Neutralization reaction a) A and D b) B and D c) A and C

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

Which of the following is not a physical change? a) Boling of water to give water vapour b) Melting of ice to give water c) Dissolution of salt water d) Combustion of liquefied petroleum gas

Posted by Hirenya A 3 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Srijan P 3 years, 4 months ago

Say truly in which class do u

ANSWER

In which class structure of atom, configuration of electron of a element, their division is there ?

Posted by Hindu ?? 3 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

What will happen if you make a hole in a polythene or plastic container containing a fluid explain why?

Posted by Palak Burman 3 years, 5 months ago

CBSE > Class 08 > Science

0 answers

ANSWER

Why rayon is different from synthetic fibres

Posted by Rishabh Srivastava 3 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Vani Thakur 3 years, 5 months ago

Rayon is different from the other synthetic fibres bcs it is made up of wood pulp. By the chemical treatment of natural substance that's wood pulp

ANSWER

What is fermentation process

Posted by Rishabh Srivastava 3 years, 5 months ago

CBSE > Class 08 > Science

1 answers

Sia ? 3 years, 5 months ago

Fermentation is a metabolic process that produces chemical changes in organic substrates through the action of enzymes. In biochemistry, it is narrowly defined as the extraction of energy from carbohydrates in the absence of oxygen.

ANSWER

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