WHAT ARE REDUCING AGENTS OXIDISING AGENTS - EASY ANALYSIS

 

 A reducing agent is a substance that reduces another substance by:

• giving hydrogen to the substance
• removing oxygen from the substance
• giving electrons to the substance

In the process of reducing another substance, the reducing agent itself becomes oxidised.

Common Reducing Agents are:

• Potassium iodide, KI (colourless solution)
• Reactive metals such as Mg, Zn, Al
  
• Hydrogen gas, H₂
• Carbon, C
• Carbon monoxide, CO
• Hydrogen sulfide, H₂S
• Sulfur dioxide, SO₂

Test for Oxidising Agent: Use of a Reducing Agent e.g. aqueous potassium iodide, KI(aq)  Observation: Colourless solution turns brown.

Chemistry behind it: 2I^–(aq) => I₂(aq) + 2e^–

^{******************************************************************************************************}

An oxidising agent is a substance that oxidises another substance by

• giving oxygen to the substance
• removing hydrogen from the substance
• receiving electrons to the substance

In the process of oxidising another substance, the oxidising agent itself becomes reduced

Common Oxidising Agents are:

• Acidified potassium manganate (VII), KMnO₄ (purple solution)
• Acidified potassium dichromate (VI), K₂Cr₂O₇ (orange solution)
• Halogens e.g. Cl₂, Br₂
• Concentrated Sulfuric acid, H₂SO₄
• Nitric acid, HNO₃
• Oxygen, O₂

Test for Reducing Agent: Use of an Oxidising Agent e.g. acidified potassium manganate (VII). Observation: Purple solution decolourises.

Chemistry behind it: MnO₄^–(aq) + 8H⁺(aq) + 5e^– => Mn²⁺(aq) + 4H₂O(l)

USEFULNOTES_PDF

 

 

 SHORT STORIES - CLASS 10 ICSE - ENGLISH 1 - SAMPLE

 

Write an original story. Short story entitled - The Secret

Write an original short story entitled- The Narrow Escape

Write an original short story entitled - man is often ruined by his pride.

Write an original short story entitled - escaped.

Write an original short story, entitled - lost and found.

Write an original short story entitled- My sanity was restored.

Write an original short story entitled - regret, but too late to repent.

Write an original short story entitled- The Gift

Write an original short story entitled - I want, but don't always get.

I'll write an original short story entitled - The Hand That Rocks the Cradle rules the world.

Write an original short story based on a joint family.

Write an original short story entitled - self-help is the best help.

Write an original short story beginning with - one cold Frosty morning in the lonely island...

Write an original short story, which has the following characters - a capseller, a passerby, a stray dog, a mad man and a dwarf. 

 

MERCHANT OF VENICE (MOV) ICSE QUESTIONS AND ANSWERS_GUIDE_CLASS 9 CLASS 10_PAPER 2

 

MERCHANT OF VENICE (MOV) ICSE QUESTIONS AND ANSWERS_GUIDE_CLASS 9 CLASS 10_ENGLISH LITERATURE_PAPER 2

CLICKHEREFORLINK

TAGS: icse merchant of venice questions and answers pdf

merchant of venice class 9 icse question paper

merchant of venice guide book icse pdf free download

merchant of venice class 9 icse workbook answers

merchant of venice extract questions

multiple choice questions on icse class 9 merchant of venice workbook answers pdf download

merchant of venice question answers

SELINA CHAPTER 20 SOLUTIONS_ EX 20B , 20E , 20F , 20G _MENSURATION 

CLICKHEREFORNOTESPDF

EXERCISE 20(B)
    
   10. A solid cone of height 8 cm and base radius
     6 cm is melted and recast into identical cones,
     each of height 2 cm and diameter 1 cm. Find
     the number of cones formed.

    11. The total surface area of a right circular cone of slant height 13 cm is 90 pi cm2.
Calculate :
      i) its radius in cm.
     (ii) its volume in cm3. [Take = 3-14] .

 
    13. A vessel, in the form of an inverted cone, is
      filled with water to the brim. Its height is
      32 cm and diameter of the base is 25-2 cm.
      Six equal solid cones are dropped in it, s
      that they are fully submerged. As a result,
     one-fourth of water in the original cone
      overflows. What is the volume of each of the
      solid cones submerged ?

   '14 The volume of a conical tent is 1232 M3 and
     the area of the base floor is 154 m2. Calculate
      the
      (i) radius of the floor,
      (ii) height of the tent,
      (iii) length of the canvas required to cover this conical tent if its width is 2 m.
     

EXERCISE 20 D

10. A solid metallic cone, with radius
  6 cm and height 10 cm, is made of
  some heavy metal A. In order to
  reduce its weight, a conical hole is
made in the cone as shown and it
  is completely filled with a lighter metal. THE
  conical hole has a diameter of 6 cm and depth
   cm. Calculate the ratio of the volume of metal
  A to THE volume of the metal B in the solid.

EXERCISE 20(E)


              3. From a rectangular solid of metal 42 cm by
                           30 cm by 20 cm, a conical cavity of diameter
                      14 cm and depth 24 cm is drilled out. Find :

                     (1) the surface area of remaining solid,
                       (ii) the volume of remaining solid,
                     (iii) the weight of the material drilled out
                             weighs 7 gm per cm^3.                                    


EXERCISE 20(F)


4. A circus tent is cylindrical to a height of 8 m
  surmounted by a conical part. If total height
  of the tent is 13 m and the diameter of its base
  is 24 m; calculate
   i) total surface area of the tent,8.
  (ii) area of canvas, required to make this tent
     allowing 10% of the canvas used for folds
     and stitching.

7. A wooden toy is in the shape of
  a cone mounted on a cylinder as
  shown alongside.
  If the height of the cone is 24 cm,
  the total height of the toy is 60 cm
  and the radius of the base of the
  cone = twice the radius of the base of the cylinder
  = 10 cm: find the total surface area of the toy.
  [Take pi= 3-14]

13.                        An open cylindrical vessel of internal diameter
                               cm and height 8 cm stands on a horizontal
                         table. Inside this is placed a solid metallic right
                         circular cone. the diameter of whose base is
                                       cm and height 8 cm. Find the volume of
                         water required to fill the vessel.
                         If this cone is replaced by another cone,
                          whose height is 1 3/4 cm and the radius of whose
                     base is 2 cm, find the drop in the water level.


EXERCISE 20(F)

7. An iron pole consisting of a cylindrical portion
   110 cm high and of base diameter 12 cm is
  surmounted by a cone 9 cm high. Find
      the mass of the pole, given that 1 cm^3 of iron
has 8 gm of mass (approx). (Take pi=355/113)

10. A cylindrical water tank of diameter 2.8 m and
  height 4.2 m is being fed by a pipe of
  diameter 7 cm through which water flows at
  the rate of 4 m/s . Calculate, in minutes, the
  time it takes to fill the tank.

11. Water flows, at 9 km per hour, through a
  cylindrical pipe of cross-sectional area 25 cm^2.
  If this water is collected into a rectangular
  cistern of dimensions 7.5 m by 5 m by 4 m;
  calculate the rise in level in the cistern in
 1 hour 15 minutes.


  15. An exhibition tent is in the form of a cylinder   surmounted by a cone.
The height of the tent
   surmounted by a cone. The height of the tent
    above the ground is 85 m and height of the
    cylindrical part is 50 m. If the diameter of the  
  base is 168 m, find the quantity of canvas
    base is 168 m, find the quantity of canvas
    required to make the tent. Allow 20% extra for
    fold and for stitching. Give your answer to the
    nearest m^2.       [2001]


         20. A conical tent is to accomodate 77 persons.
             Each person must have 16m^3 of air to
             breathe. Given the radius of th ent as 7 m,
is total     find the height of the tent and also its curved
             surface area.                   

 

CAMBRIDGE CHECKPOINT MATHEMATICS CLASS 8 EX 15.3 ANSWERS_2013 EDITION

 EX 15.3 SOLUTIONS

 

 I Xavier throws two fair dice together. What is the probability of scoring:
   a two fours
b no fours  
c exactly one four?
 2 Mia throws two fair dice and adds the scores.
   a What is the smallest possible total?
   b What is the largest possible total?       
   c What is wrong with Mia's argument          

3 Shen throws two dice and adds the numbers together.
   a What is the most likely possible total?        
b What is the least likely possible total?
   Find the probability that the total will be:
   c 2 d 7 e less than 7 f an odd number                             g a prime number.

4 Razi throws two dice. Find the probability that:
   a the numbers are the same       b the difference between the two numbers is 2.

5 Dakarai spins a coin and throws a dice. One possible outcome is a head and a 6.
   a Show that there are 12 mutually exclusive outcomes and list them in a table.
   b Find the probability of scoring:
     i a tail and a 1      ii a head and an even number        iii a tail and a or a 6.

6 Alicia has two three-sided spinners.
   One shows the numbers 1, 1, 3.
   The other shows the numbers 2, 3, 5.                                   2   3    5
   a Copy and complete the table to show
     the total score of the two spinners.                                     4
   b Find the probability of a total of:
     i 3       ii 6       iii 5 or more     iv an even number.

7 Oditi throws two dice and multiplies the scores together.
   a Draw a table to show the possible values of the product.          The product is the result of
   b How many different products are possible?                         multiplying two numbers.
   c Find the probability that the product is
     i 12      ii not 12      iii less than 12    iv more than 17       v an even number.

8 Hassan has four blue pens and a red pen in his pocket.
   He takes out one without looking, and then he                    Second pen
   takes another.                                                a Copy and complete the table to show the possible
     selections.                                    
   b Why are there Xs down the diagonal?
   c Find the probability that:
     i both pens are blue ii the first pen is red         
     iii one of the pens is red.

9 Shen and Tanesha play crock, paper, scissors. They simultaneously make a sign for one of the items.
   a Make a table to show the different possible outcomes.
   b If each person chooses at random, what is the probability that they will not choose the same
     thing?
   c Rock beats scissors. Scissors beat paper. Paper beats rock. What is the probability Shen beats
     Tanesha, if they play one game?