Advertisements
Advertisements
प्रश्न
A shiny brown-coloured element ‘X’ on heating in air becomes black in colour. Name the element ‘X’ and the black-colored compound formed.
उत्तर १
X’ is copper (Cu) and the black-coloured compound formed is copper oxide (CuO). The equation of the reaction involved on heating copper is given below.
\[\ce{2Cu + O2 ->[Heat] 2CuO}\]
उत्तर २
The shiny brown-colored element is the copper metal (Cu). When the metal is heated in the air, it reacts with the atmospheric oxygen to form copper oxide. Hence, the black-colored compound is copper oxide, (CuO).
\[\ce{2Cu_{(s)} + O2_{(g)} ->[\Delta] 2CuO_{(s)}}\]
APPEARS IN
संबंधित प्रश्न
What is an oxidising agent?
Write the chemical formula of rust.
Is oxidation an exothermic or an endothermic reaction?
When copper powder is heated strongly in air, it forms copper oxide. Write a balanced chemical equation for this reaction. Name (i) substance oxidised, and (ii) substance reduced.
Fill in the blank
Oxidation is the removal of ......................and addition of ....................
TRUE \ FALSE
Hydrogen is a good oxidizing agent.
Explain the following in term of gain or loss of oxygen with two examples.
Reduction
Divide the following reactions into oxidation and reduction half-reaction:
Zn + Cu2+ → Cu + Zn 2+
Name:
a substance that oxidizes concentrated HCl to chlorine.
Complete and balance the following equation:
CuO +__________→ Cu +___________
Complete and balance the following equation:
\[\ce{K + H2O -> }\]________+ ________
Select the correct answer from the symbol in the bracket.
The element, which like hydrogen is a strong reducing agent.
When the positive charge on an ion increases or the negative charge on them decreases it is called as _______.
Identify the reducing agent in the following reactions
`"Fe"_2"O"_3 + 3"CO" -> 2"Fe" + 3"CO"_2`
During the reaction of some metals with dilute hydrochloric acid, following observations are made.
The temperature of the reaction mixture rises when aluminium (Al) is added.
Explain this observation giving suitable reason.
Zinc liberates hydrogen gas when reacted with dilute hydrochloric acid whereas copper does not. Explain why?
Find the oxidation number of the element in the following compound.
Mg in MgO
Identify the type of chemical reaction given below:
\[\ce{2Mg + O2 -> 2MgO}\]
