Advertisements
Advertisements
प्रश्न
Identify from the reaction the reactants that undergo oxidation and reduction.
2Mg + O2 → 2MgO
\[\ce{2Mg + O2 ->[\Delta] 2MgO}\]
Advertisements
उत्तर १
In a reaction, magnesium is changing to magnesium oxide. That means, oxygen is being added to magnesium. Addition of oxygen to a substance is called oxidation, so magnesium undergoes oxidation.
उत्तर २
Mg undergoes oxidation and O2 undergoes reduction.
APPEARS IN
संबंधित प्रश्न
Define ‘redox reaction’. Give one example.
What is an oxidising agent?
Explain the following in term Oxidation of gain or loss of oxygen with two example.
A shiny brown-coloured element ‘X’ on heating in air becomes black in colour. Name the element ‘X’ and the black-colored compound formed.
What is meant by rust?
Why is photosynthesis considered an endothermic reaction?
What are anti-oxidants?
Identify the component oxidised in the following reaction:
\[\ce{H2S + Cl2 -> S + 2HCl}\]
When SO2 gas is passed through saturated solution of H2S, the following reaction occurs:
\[\ce{SO2 + 2H2S -> 2H2O + 3S}\]
In this reaction, which substance is oxidised and which one is reduced?
In the reaction represented by the equation:
\[\ce{MnO2 + 4HCl -> MnCl2 + 2H2O + Cl2}\]
- name the substance oxidised.
- name the oxidising agent.
- name the substance reduced.
- name the reducing agent.
Is oxidation an exothermic or an endothermic reaction?
Explain the following in terms of gain or loss of oxygen with one example:
Oxidation
Explain the following in terms of gain or loss of oxygen with one example:
Reduction
In the context of redox reactions, the removal of hydrogen from a substance is known as ______.
In order to prevent the spoilage of potato chips, they are packed in plastic bags in an atmosphere of ______.
You are given the following chemical equation:
\[\ce{Mg_{(s)} + CuO_{(s)} -> MgO_{(s)} + Cu_{(s)}}\]
This equation represents:
Hydrogen burns with a ______ flame and ______ sound is heard.
Fill in the blank
In redox reaction oxidation and reduction occur ............................
Indicate which of the following statement is true and which is false:
The removal of hydrogen from a substance is called reduction.
Define an oxidation reaction.
Define redox reaction.
MULTIPLE CHOICE QUESTIONS
The process of adding oxygen to a substance is called
- oxidation.
- reduction.
- displacement.
- hydrogenation.
Identify the substances that are oxidised and the substances that are reduced in the following reaction.
\[\ce{CuO_{(s)} + H2_{(g)} -> Cu_{(s)} + H2O_{(l)}}\]
Explain the following in term Reduction of gain or loss of oxygen with two example.
The electron releasing tendency of zinc is ______ than that of copper.
The colours of aqueous solutions of CuSO4 and FeSO4 as observed in the laboratory are:
(A) pale green and light blue respectively
(B) light blue and dark green respectively
(C) dark blue and dark green respectively
(D) dark blue and pale green respectively
Identify from the following reaction the reactants that undergo oxidation and reduction.
\[\ce{2Ag2O → 4 Ag + O2 \uparrow}\]
Explain the following in term of gain or loss of oxygen with two examples.
Reduction
In what respect does hydrogen differ from:
alkali metals
State whether the following conversion is oxidation or reduction:
PbO2 + SO2→ PbSO4
State whether the following conversion is oxidation or reduction:
K → K+ + e-
State whether the following conversion is oxidation or reduction:
2Cl- - e-→ Cl2
In the following reaction: A+ + B → A + B+. Write half-reactions for this reaction and name:
- oxidizing agent
- substance oxidized
- reducing agent
Write the equation in the ionic form
CuSO4(aq) + Fe(s)→ FeSO4(aq) + Cu(s)
Reacting with water, an active metal produces
Choose terms from the options given in brackets to complete this sentence.
When CuO reacts with hydrogen,………………… is reduced and ……………….is oxidized to ………………….
(CuO, H2, Cu, H2O)
Complete and balance the following equation:
CuO +__________→ Cu +___________
With reference to oxidation & reduction reaction – complete the statement given by filling in the blanks with only the words (a) Addition (b) Removal.
‘Oxidation is a chemical reaction involving ____ of oxygen to a substance or ____ of hydrogen from a substance. Reduction on the otherhand involves ____ of hydrogen to a substance or ____ of oxygen from a substance.
Explain the term oxidation in term of addition and removal of oxygen/hydrogen with a suitable example.
Explain the term reduction in term of addition and removal of oxygen/hydrogen with a suitable example.
Explain the following reaction with their balanced chemical equation.
Hydrogen sulphide reacts with sulphur dioxide.
Select the oxidising agent for the following reaction:
\[\ce{H2S + I2 -> 2HI + S}\]
Identify the oxidising agent (oxidant) in the following reactions
`"CuSO"_4 + "Zn" -> "Cu" + "ZnSO"_4`
Identify the oxidising agent (oxidant) in the following reactions.
`"CuO" + "H"_2 -> "Cu" + "H"_2"O"`
Which among the following are physical or chemical change?
Evaporation of petrol
Which among the following are physical or chemical change?
Heating of an iron rod to red hot
During the reaction of some metals with dilute hydrochloric acid, following observations are made.
Some bubbles of a gas are seen when lead (Pb) is reacted with the acid.
Explain this observation giving suitable reason.
Zinc liberates hydrogen gas when reacted with dilute hydrochloric acid whereas copper does not. Explain why?
The tendency of atoms to have eight electrons in the outer shell is known as ______.
Define oxidation number.
Find the oxidation number of the element in the following compound.
Zn in ZnSO4
Identify the type of chemical reaction given below:
\[\ce{2Mg + O2 -> 2MgO}\]
A reddish brown metal used in electrical wires when powdered and heated strongly turns black. When hydrogen gas is passed over this black substance, it regains its original colour. Based on this information answer the following questions:
- Name the metal and the black substance formed.
- Write balanced chemical equations for the two reactions involved in the above information
The metallic oxide which can be reduced by using common reducing agents is ______.
