General Science Mixed Quiz: Set 120

With no work done, the first law of thermodynamics reduces to ΔU = Q, so the change in internal energy equals the heat that flows in or out.

The 2011 FSSAI labelling rules made the list of ingredients, nutrition information and the vegetarian or non-vegetarian mark compulsory, but not medical advice on allergies.

For reflection at a plane mirror, the deviation is 180° − 2i, and with i = 40° this gives 180° − 80° = 100°.

Meiosis halves them in the gametes, and fertilisation restores them in the offspring. Each parent makes gametes by meiosis, so a human egg or sperm carries 23 chromosomes instead of 46.

The thunder arrived 6 seconds after the flash, and sound covers 320 m every second, so the distance is 320 × 6 = 1920 m. Lightning and thunder are produced at the same moment.

Friction acts only where two surfaces touch, while a magnet can push or pull an object across a gap. Forces are grouped by whether the bodies must touch.

Resistivity equals resistance multiplied by area and divided by length, which leaves the unit ohm × length.

For an ideal gas in a fixed volume at a fixed temperature, pressure is proportional to the number of molecules, so half the molecules give half the pressure.

The sulphide ion has 16 + 2 = 18 electrons, and its mass number of 32 is its count of nucleons.

Crown gall is caused by the bacterium Agrobacterium tumefaciens, which enters through a wound near the base, or crown, of the stem and makes the plant grow rough tumour-like swellings there.

Iron is more reactive than copper, so it pushes copper out of copper sulphate, and the freed copper coats the nail brown.

Above the threshold, the kinetic energy of the ejected electrons rises as the frequency of the light rises, so the statement that it does not change is wrong.

Pure water is neutral, and a neutral solution has a pH of 7 at 25 °C. pH is the negative logarithm of the hydrogen ion concentration.

Two ammonium ions, each with a charge of +1, are needed to balance one carbonate ion with a charge of -2.

Lithium hydrogen carbonate exists only in solution; it cannot be isolated as a solid. All the alkali metals of group 1 form hydrogen carbonates (bicarbonates), but lithium behaves differently from the rest.

The pericycle is a layer of cells around the vascular cylinder of the root and stem; it is not part of xylem or phloem.

In the alkane series the boiling point rises as the carbon chain gets longer, and this order goes from 3 to 4 to 5 to 8 carbons.

Lemon juice is acidic and rich in vitamin C, which together slow the enzyme reaction that browns cut apple. When an apple is cut, the enzyme polyphenol oxidase in its cells meets oxygen in the air and oxidises the fruit's phenolic compounds into brown pigments (melanins).

Its network of membrane tubes and sheets forms channels that carry materials, especially proteins, between parts of the cytoplasm and the nucleus.

It is part of the kidney's nephron and filters blood to form urine; it plays no role in breathing. Bowman's capsule is the cup-shaped start of each nephron, wrapped around a tuft of capillaries called the glomerulus.