Everyday Science

Petrol evaporates faster than water at room temperature primarily because petrol molecules do not form hydrogen bonds, unlike water molecules which have strong hydrogen bonding. This reduces the intermolecular forces in petrol, allowing its molecules to escape into the vapor phase more easily.

A yard is approximately 0.9144 meters, so 1 meter is the closest option to a yard in length among the given choices.

Oranges are well known for being rich in vitamins, particularly vitamin C, which supports immune function and skin health. They contain minimal fats and proteins, and while they have carbohydrates, vitamins are their most notable nutrient.

Cow milk is a rich source of vitamin A, which is important for vision and immune function. It contains lower amounts of vitamin C, and while it has some B vitamins, vitamin A is notably abundant compared to the other options.

Children aged 1 to 3 years typically require between about 1,000 and 1,400 kilocalories per day to support their growth and activity levels. The amount of 300 kilocalories is far too low for this age group. The option '1200 k Calories' best reflects the typical energy requirement for children aged 1 to 3 years, aligning with standard nutritional guidelines and recommendations from authoritative health sources such as the CDC and WHO.

Carbon dioxide is used in the preparation of soft drinks to provide carbonation, which gives the drinks their fizz and slightly acidic taste.

In scientific work, both precision (consistency of results) and accuracy (closeness to the true value) are important and should be maintained together to ensure reliable and valid results. Options B and C incorrectly suggest that one is essential while the other is not, and option D is not necessarily true as calculations may be done before, during, or after experiments depending on the context.

Weather refers to the atmospheric conditions such as temperature, humidity, precipitation, and wind at a specific place and time. Therefore, it describes the condition of the atmosphere at any one time.

Heating a liquid increases the kinetic energy of its molecules, which makes more molecules able to escape into the vapor phase, thus increasing the vapor pressure.

Wood is an insulator and does not conduct electricity well, whereas copper and iron are good conductors, and water can conduct electricity due to dissolved ions. Therefore, wood is the least conductor among the options.