Advertisements
Advertisements
प्रश्न
Which among the following are physical or chemical change?
Curding of milk
Advertisements
उत्तर
Chemical
APPEARS IN
संबंधित प्रश्न
Corrosion can be prevented by using ……………. solution.
Define corrosion.
Write the chemical formula of rust.
In the reaction represented by the equation:
MnO2 + 4HCl → MnCl2 + 2H2O + Cl2
(i) name the substance oxidised.
(ii) name the oxidising agent.
(iii) name the substance reduced.
(iv) name the reducing agent.
Hydrogen burns with a ______ flame and ______ sound is heard.
Name the following:
The process in which oxygen is added or hydrogen is removed.
Define redox reaction.
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+
Write chemical formula for rust.
Find the oxidation number of the elements in the following compounds.
- C in CO2
- Mn in MnSO4
- N in HNO3
Identify the reducing agent in the following reactions -
`"H"_2"O" + "F"_2 -> "HF" + "HOF"`
Identify the oxidising agent (oxidant) in the following reactions
`"Pb"_3"O"_4 + 8"HCl" -> 3"PbCl"_2 + "Cl"_2 + 4"H"_2"O"`
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.
What happens when zinc granules are treated with dilute solution of H2SO4, HCl, HNO3, NaCl and NaOH Also write the chemical equations if reaction oçcurs.
Find the oxidation number of the element in the following compound.
A1 in AlCl3
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
