Which among the following will be named as dibromidobis (ethylene diamine) chromium(III) bromide?

Iron exhibits + 2 and +3 oxidation states. Which of the following statements about iron is incorrect?

The molecule having smallest bond angle is :

For a first order reaction, (A) $$\to$$ products, the concentration of A changes from 0.1 M to 0.025 M in 40 minutes. The rate of reaction when the concentration of A is 0.01 M is :