Class 10 Science1)
Which one of the following processes involve chemical reactions?
Heating copper wire in presence of air at high temperature.
Class 10 Science2)
A teacher gave two test tubes to the students, one containing water and the other containing sodium hydroxide. She asked them to identify the test tube containing sodium hydroxide solution. Which one of the following can be used for the identification?
Class 10 Science3)
Which of the following is not physical change?
Combustion of Liquefied Petroleum Gas (LPG)
Class 10 Science4)
Barium chloride on reacting with ammonium sulphate forms barium sulphate and ammonium chloride. Which of the following correctly represents the type of the reaction involved?
precipitation and double displacement reaction
Class 10 Science5)
Which of the following is true for an unbalanced chemical equation?
Both (b) and (c)
Class 10 Chemistry6)
Which option denotes a double displacement reaction?
AC + BD → AD + BC
Class 10 Chemistry7)
Electrolysis of water is a decomposition reaction. The mole ratio of hydrogen and oxygen gases liberated during electrolysis of water is
Class 10 Chemistry8)
Which of the following is Not True with respect to the neutralisation reaction?
Reactants are in gaseous state
Class 10 Chemistry9)
In the double displacement reaction between aqueous potassium iodide and aqueous lead nitrate, a yellow precipitate of lead iodide is formed. While performing the activity if lead nitrate is not available, which of the following can be used in place of lead nitrate?
Class 10 Chemistry10)
When do you use double arrow in a chemical equation?
When reaction is reversible.