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Shivani siva
@shivani-siva
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Joined: Aug 6, 2021
Last seen: Sep 10, 2021
Topics: 289 / Replies: 1732
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Answer to: Balance the following chemical equations: (a) HNO3 + Ca(OH)2 ➝ Ca(NO3)2 + H2O (b) NaOH + H2SO4 ➝ Na2SO4 + H2O

(a) 2HNO3 + Ca(OH)2 ➝ Ca(NO3)2 + 2H2O (b) 2NaOH + H2SO4 ➝ Na2SO4 + 2H2O (c) The symbolic equation as given for the reaction is already balanced. ...

4 years ago
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Answer to: Difference between Distance and Displacement.

(i) Distance is a scalar quantity whereas displacement is a vector quantity. (ii) Distance is the total path covered by the body and displacement i...

4 years ago
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Answer to: Difference between Speed and Velocity.

Speed: (i) Speed is simply the rate of change of motion. (ii) Speed is the distance traveled by a body in a unit time. (iii) Speed is a scalar ...

4 years ago
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Answer to: A train starting from a railway station and moving with uniform acceleration attains a speed of 40 k/hr in 10 minutes. Find its acceleration in the units of m/s.

Given, t = 10 min = 10 x 60 = 600 s Initial speed of train is given as u = 0 m/s Final speed of train as v = 40 k/h = = 11.1 m/s Now accele...

4 years ago
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Answer to: Which statement is true? (a) distance is a vector quantity (b) magnitude of distance is smaller than displacement (c) magnitude of is equal to magnitude of displacement

Correct answer: (c) magnitude of is equal to magnitude of displacement Explanation: When an object moves in a straight line in the fixed directio...

4 years ago
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Answer to: Under what condition is the magnitude of average velocity of an object equal to its average speed?

Correct answer: (A) object travel in Straight line Explanation: The magnitude of the average velocity of an object is equal to its average speed, ...

4 years ago
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Answer to: Give five point of difference between prokaryotic cells and eukaryotic cells. Explain it.

Prokaryotic Cells: 1. They are unicellular organisms, size ranges from 0.2μm – 2.0 μm in diameter. 2. The cell wall is present but chemically comp...

4 years ago
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Answer to: Explain hypertonic solution and isotonic solution.

Hypertonic solution is the one which has higher osmotic concentration and less solvent concentration as compared to another solution. Isotonic solu...

4 years ago
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Answer to: Transfer the following into chemical equations and balance them: (a) Hydrogen gas combines with nitrogen to form ammonia. (b) Hydrogen sulphide gas burns in air to give water and sulphur dioxide.

(a) The symbol equation for the reaction is: H2 + N2 ➝ NH3 The balancing of equation is done in the following steps: Step I: Let us count the nu...

4 years ago
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Answer to: What is a balanced chemical equation? Why should chemical equations be balanced?

A chemical equation is said to be balanced if: (a) the atoms of different elements on both sides of the equations are equal. (b) the equation is m...

4 years ago
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Answer to: Magnesium ribbon burns with a dazzling flame in air (or oxygen) and changes to a white substance magnesium oxide. Is magnesium being oxidised or reduced in this reaction?

The balanced chemical equation is: 2Mg(s) + O2(g) ➝ 2MgO(s) Yes, magnesium (Mg) gets oxidised to form magnesium oxide (MgO) in this reaction is sa...

4 years ago
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Answer to: Identify the substances that are oxidised and the substances that are reduced in the following reactions:

(a) In this reaction, sodium (Na) is oxidised to sodium oxide (Na2O). This means that oxygen (O2) gets reduced. (b) In this reaction, hydrogen (H2) ...

4 years ago
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Answer to: Give one example of the double displacement reaction.

BaCl2(aq) + CuSO4(aq) → BaSO4(s) + CuCl2(aq)

4 years ago
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Answer to: Why does the colour of copper sulphate change when an iron nail is dipped in it?

Iron nail acquires a brown coating of copper as a result of displacement reaction. The solution becomes light green. Fe(s) + CuSO4(aq) → FeSO4(aq) +...

4 years ago
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Answer to: When you mix solutions of lead (II) nitrate and potassium iodide. (a) What is the colour of the precipitate formed? Name the compound involved. (b) Write a balanced chemical equation for the reaction.

(a) The precipitate is yellow in colour. The compound is lead(II) iodide with chemical formula PbI2. (b) Pb(NO3)2(aq) + 2KI(aq) ➝ Pbl2(s) + 2KNO3(aq...

4 years ago
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Answer to: Why is the amount of gas collected in one of the test tubes in Activity 7 double of the amount collected in the other? Name the gas.

It is so because in water, the hydrogen is two times more than oxygen by mass and volume. The equation is expressed as: 2H2O(aq) + Electrolysis →...

4 years ago
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