Advertisements
Advertisements
Question
Write chemical formula for rust.
Advertisements
Solution
Chemical formula for rust: Fe2O3•xH2O
APPEARS IN
RELATED QUESTIONS
Define ‘redox reaction’. Give one example.
What is an oxidising agent?
Which of the statements about the reaction below are incorrect?
\[\ce{2PbO(s) + C(s) → 2Pb(s) + CO2(g)}\]
- Lead is getting reduced.
- Carbon dioxide is getting oxidised.
- Carbon is getting oxidised.
- Lead oxide is getting reduced.
Define corrosion.
Why is photosynthesis considered an endothermic reaction?
Identify in the following reaction (a) the substance oxidised, and (b) the substance reduced:
\[\ce{ZnO + C -> Zn + CO}\]
When a magnesium ribbon burns in air with a dazzling flame and forms a white ash, is magnesium oxidised or reduced? Why?
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.
Give an example of an oxidation reaction.
Is oxidation an exothermic or an endothermic reaction?
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 ______.
Fill in the blank
Oxidation is the removal of ......................and addition of ....................
Define redox reaction.
TRUE \ FALSE
Hydrogen is a good oxidizing agent.
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.
Electrolysis is a redox process. Explain.
How would you change a metal like Cu into its ions?
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
Explain the following in term of gain or loss of oxygen with two examples.
Oxidation
Explain the following in term of gain or loss of oxygen with two examples.
Reduction
Is it essential that oxidation and reduction must occur side by side in a chemical reaction? Explain
State, giving reason, whether the substances printed in bold letters have been oxidized or reduced.
Mg + 2HCl → MgCl2 + H2
State, giving reason, whether the substances printed in bold letters have been oxidized or reduced.
H2S + Cl2→ 2HCl + S
In the following reaction: A+ + B → A + B+. Write half-reactions for this reaction and name:
- oxidizing agent
- substance oxidized
- reducing agent
Divide the following reactions into oxidation and reduction half-reaction:
Zn + Pb2+→ Pb + Zn 2+
Divide the following reactions into oxidation and reduction half-reaction:
Zn + Cu2+ → Cu + Zn 2+
Divide the following reactions into oxidation and reduction half-reaction:
Cl2 + 2Br- → Br2 + 2Cl-
Divide the above equation into oxidation and reduction half-reactions.
A metal oxide that is reduced by hydrogen is
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)
Name:
a substance that will reduce aqueous Iron(III)ions to iron(II)ions.
Name:
a solid that is an oxidizing agent.
Complete and balance the following equation:
Fe + H2O →___________+____________
State a reason why, when hydrogen is passed over heated copper oxide, the resultant product formed, differs in colour from the original reactant.
When the positive charge on an ion increases or the negative charge on them decreases it is called as _______.
Balance the given chemical reaction as per the instructions below.
\[\ce{NaOH + H2SO4 -> Na2SO4 + H2O}\]
Oxidation means losing electrons then what is reduction?
Oxidising agents are also called as ______ because they remove electrons form other substances.
Which of the following statements about the given reaction are correct?
\[\ce{3Fe_{(s)} + 4H2O_{(g)} -> Fe3O4_{(s)} + 4H2_{(g)}}\]
(i) Iron metal is getting oxidised.
(ii) Water is getting reduced.
(iii) Water is acting as the reducing agent.
(iv) Water is acting as oxidising agent.
Select the oxidising agent for the following reaction:
\[\ce{H2S + I2 -> 2HI + S}\]
Identify the reducing agent in the following reactions
`4"NH"_3 + 5"O"_2 -> 4"NO" + 6"H"_2"O"`
Identify the oxidising agent (oxidant) in the following reactions
`"CuSO"_4 + "Zn" -> "Cu" + "ZnSO"_4`
Which among the following are physical or chemical change?
Heating of an iron rod to red hot
Which among the following are physical or chemical change?
Sublimation of solid ammonium chloride
On adding a drop of barium chloride solution to an aqueous solution of sodium sulphite, white precipitate is obtained :
- Write a balanced chemical equation for the reaction involved.
- What other name can be given to this precipitation reaction?
- On adding dilute hydrochloric acid to the reaction mixture, white precipitate disappears. Why?
Write a short note on oxidizing and reducing agents.
What is a redox reaction?
The formation of brown colour on the freshly unit surface of vegetables and fruits is because ______ of organic compounds present in them.
The sum of the oxidation number of all atoms in a compound is ______.
Choose the odd one out and write the reason:
Define oxidation number.
Find the oxidation number of the element in the following compound.
Zn in ZnSO4
Find the oxidation number of the element in the following compound.
Mg in MgO
It is recommended to use air tight containers for storing oil for a long time.
