Chemistry Online Quiz

Specific heat is defined by the amount of heat needed to raise the temperature of 1 gram of a substance 1 degree Celsius (°C). Lithium has the highest specific heat capacity of any solid element.

If there is no carbon dioxide (CO₂) in the earth's atmosphere, the temperature of the earth's surface would be less than the present. CO₂ is an important greenhouse gas that helps to trap heat in our atmosphere. Without it, our planet would be very cold.

Rusting is an oxidation reaction. The iron reacts with water and oxygen to form hydrated iron(III) oxide, which we see as rust. Hence, iron rust when they come into contact with water and oxygen – both are needed for rusting to occur.

Flint glass is optical glass that has relatively high refractive index and low Abbe number (high dispersion). For this reason, it is used for making the lens and prism.

Pyrex is low-thermal-expansion borosilicate glass. It is a type of glass that is resistant to heat, chemicals, and electricity. Borax is used for the extra strength of pyrex glass.

The main gases responsible for the greenhouse effect include carbon dioxide, methane, nitrous oxide, and water vapor (which all occur naturally), and fluorinated gases (which are synthetic). Bacteria are responsible for both the production and consumption of greenhouse gases such as carbon dioxide (CO₂), nitrous oxide (N₂O) and methane (CH₄).

When a helium atom loses an electron it becomes a positive helium ion. When an atom gains/loses an electron, the atom becomes charged, and is called an ion. If a neutral atom gains an electron, it becomes negative. This kind of ion is called an anion. If a neutral atom loses an electron, it becomes positive. This kind of ion is called a cation.

Magnesium is present in seawater in amounts of about 1300 ppm. The six most abundant ions of seawater are chloride (Cl⁻), sodium (Na⁺), sulphate (SO²₄⁻), magnesium (Mg²⁺), calcium (Ca²⁺), and potassium (K⁺). By weight, these ions make up about 99 percent of all sea salts.

Lactic Acid is an organic acid with the chemical formula C₃H₆O₃. Curd is sour due to the presence of Lactic acid. When milk sugar or lactose undergoes fermentation, the product obtained is lactic acid.

The process of improving the quality of rubber by heating it with sulphur is called Vulcanization. It is the process of converting natural rubber to more strong and more elastic form.