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- Chemical Reactions & Equations
- Acid, Bases & Salts
- Metals & Non Metals
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- Periodic Classification of Elements
- Life Processes
- Respiration
- Control and Coordination
- How Do Organism Reproduce
- Heredity and Evolution
- Light: Reflection and Refraction
- Human Eye and Colorful World
- Electricity
- Magnetic Effect of Electric Current
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- Management of Natural Resources
Popular Questions
- When Ca(OH)2 reacts with CO2 (g), it will give CaCO3 (s) and H2O (I). The nature of CaCO3 is
- Assertion : While dissolving an acid or base in water Reason : Dissolving an acid on a base in water
- name an acid which is present in baking powder.
- You are having five solutions A,B,C,D and E with pH values as follows:
- (i) Define a universal indicator (ii) Solution A gives pink colour (iii) Name one salt whose solution has pH
- A milkman adds a very small amount of baking soda to fresh milk.
- Name the chemicals used in making fire extinguisher.
- Name the sodium compound which is used for softening hard water.
- Assertion : HCL produces hydronium ions Reason : In presence of water, basic gives H+ ions.
- You have two solutions a and B. the pH of solution A is 6
- The pH of a solution is 5.0. Its hydrogen ion concentration is decreased by 100 times, the solution will be:
- Assertion : Phenolphthalalein gives pink colour in basic solution Reason : Phenolphthalalein is a natural indicator
- A substance X is used as a building material and insoluble in water.
- Give two important uses of washing soda and baking soda.
- A student dipped pH paper in rain water. What would be the colour of the pH paper?
- Calcium phosphate is present in tooth enamel. Its nature is
- You have been provided with three test tubes.
- Plaster of paris should be stored in moisture proof containers. Explain why.
- A dry pellet of a common bases B when kept in open absorbs moisture and turns sticky.
- Assertion : Sodium hydroxide reacts Reason : Acids reacts with active metals
- Acetic acid was added to a solid x kept in a test tube. A colourless and odourless gas was evolved.
- Fresh milk has a pH of 6. How do you think
- Incorrect statement about acids is/are
- In one of the industrial processes used for manufacture of sodium hydroxide, a gas x is formed as by-product.
- Answer the following: (i) What happens when a concentrated solution (ii) Why is the electrolysis of a concentrated solution (iii) ..
- (i) Name one natural source of each of the following acids. (ii) Which ion is commonly produced by all acids?
- Match the chemical substances given in column (I) With their appropriate application given in column (II).
- A solution has pH of 7. Explain how would you
- The pH of a solution is 4.0. What should be the change in the hydrogen ion concentration of the solution, if its pH is to be incre..
- Give one example in each case:
- The correct Statement regarding universal indicator is
- Which gas is usually liberated when an acid reacts with a metal?
- Equal volumes of hydrochloric acid and sodium hydroxide solution of some concentration are mixed and the pH of the resulting solut..
- The pH of a salt used to make tasty and crispy pakoras is 14.
- Metal compound A reacts with dilute hydrochloric acid to produce effervescence
- 2 mL of sodium hydroxide solution is added to a few pieces of granulated zinc metal taken in a test tube.
- What is water of crystallisation? Write the common name and chemical formula of a commercially important compound which has ten w..
- (i) A chemical compound x is used in (ii) How many molecules of water of (iii) How will you prepare the above compound
- Name the substance which on treatment with chlorine yields bleaching powder
- (i) Write three physical properties each of acids and bases. (ii) How will you show with an example
