General Science Mixed Quiz: Set 180

Specific heat capacity is the heat needed to raise the temperature of a unit mass of a substance by one degree, not simply the heat needed to raise its temperature.

The cranial nerves arise from the brain and serve the head and neck, among them the optic nerve of sight, the auditory nerve of hearing, the olfactory nerve of smell and the vagus, which is the longest cranial nerve and reaches down to the heart, lungs and stomach.

Black copper(II) oxide reacts with dilute hydrochloric acid to form copper(II) chloride and water, and the solution turns blue-green because of the copper(II) ions.

In such a fluid the shearing stress is directly proportional to the rate of shear, so the coefficient of viscosity, which measures the resistance to deformation, keeps the same value whatever the stress applied; water, air, petrol and thin oils behave in this way.

Statements 1, 2 and 3 are true, but carbon never forms a quadruple, or tetra, bond between two carbon atoms.

Homi Bhabha designed the programme around the fact that India has modest uranium but very large thorium reserves in the monazite sands of the Kerala coast.

In bacteria the DNA is not wrapped around histone proteins as it is in the chromosomes of eukaryotes, so it is called naked DNA.

Doping replaces a few host atoms with impurity atoms, and each impurity atom brings its own nucleus along with its electrons, so the total positive and negative charge in the crystal stays balanced.

Smallpox was caused by the variola virus, a large DNA virus of the pox family that spread from person to person through the air.

Brass is made by alloying copper with zinc, which gives a metal harder than copper, easier to cast and machine, and resistant to ordinary corrosion, so it is used for utensils, taps and fittings and the bodies of musical instruments.

The girth, or thickness, of a stem increases only through the lateral meristems, the vascular cambium and the cork cambium.

Coal forms by the slow burial and compression of plant matter, and the longer and deeper the process goes the more carbon is left behind as moisture and volatile matter are driven off.

In the DNA double helix, adenine on one strand always pairs with thymine on the other, and guanine always pairs with cytosine.

Plastics are long chains of carbon atoms joined by strong covalent bonds, which water, air and most microbes cannot easily break.

Particles of matter mix with one another on their own, and there are forces of attraction between them; both are basic properties taught in Class 9 science.

A single-celled organism has no organs at all; the one cell takes in food through its surface or by forming temporary structures.

Kerosene and petrol mix completely with each other, and their boiling points are close, so they are separated by fractional distillation.

Buoyancy, or upthrust, is the upward force a fluid exerts on any object immersed in it. A fluid presses on an object from all sides, but the pressure grows with depth, so the push on the lower surface is greater than the push on the upper surface.

Powers of lenses in contact simply add, so the combination has a power of 2 + 2 = 4 dioptre, and its focal length is 1/4 m, that is 0.25 m. The power of a lens is the reciprocal of its focal length in metres, P = 1/f, and is…

An alloy of sodium and potassium, called NaK, stays liquid at room temperature and carries heat away from the core of some nuclear reactors.