Mercury is the only metal that is liquid at normal temperatures.

Therefore, the correct option is (C) Magnesium ribbon on burning in air produces: 'Magnesium oxide, heat and light'.

Alkali metals (lithium, sodium, potassium) are so soft that they can be cut with a knife. The freshly cut surface is a shiny, silver colour, but this tarnishes quickly to a dull grey as the metal reacts with oxygen and water in the air.

All of these diseases are caused by bacteria i.e. Pneumonia, Cholera, Tuberculosis. Cancer is caused by uncontrolled cell division. Pneumonia is caused by a bacterium Streptococcus pneumoniae. Cholera is caused by a bacterium Vibrio cholerae.

Mounting pressure from China and the United States, as well as from the Labour Party in Britain, led Prime Minister Winston Churchill to send Stafford Cripps to India to discuss the Draft Declaration, as settled by the War Cabinet and its Committee between 28 February to 9 March 1942, containing proposals to resolve ...

The correct answer is Resistance Heating. Resistance heating is based on the I2R effect and is highly resistive in nature that's why it has the maximum power factor. Electric resistance heating is defined as “the heat produced by passing an electric current through a material that preferably has high resistance”.