निम्नलिखित ईंधनों में से कौन-सा न्यूनतम वायु प्रदूषण करता है?
Which of the following fuels causes minimum air pollution?
Comprehensive collection of questions from General Science asked in recent state service examinations. Each question is verified with official answer keys and step-by-step bilingual solutions.
Which of the following fuels causes minimum air pollution?
What is the purest form of natural water?
Which of the following gases is used to purify drinking water?
The chemical formula of heavy water is:
The pH value of pure water is:
Water is a good solvent for ionic salts because:
Heavy water is a type of:
Which of the following is responsible for the permanent hardness of water?
Potable drinking water is prepared in large quantities from impure/saline water by:
In 'Heavy Water':
The process of converting saline water into pure water is called:
Which of the following catalysts is used in the hydrogenation of vegetable oils?
What is formed by burning hydrogen?
Seawater can be converted into pure water by which process?
Which of the following is not an allotrope of carbon?
By mass, the percentage of hydrogen in water ($H_2O$) is:
Which of the following is not a crystal?
Which of the following is also used as a lubricant?
The discovery of the third allotropic form of carbon was made by a team of 3 scientists who were awarded the Nobel Prize in Chemistry. Identify the one who was not in that team.
Graphene is frequently in the news. What is its importance? 1. It is a two-dimensional material and has good electrical conductivity. 2. It is one of the thinnest but strongest materials tested so far. 3. It is entirely made of silicon and has high optical transparency. 4. It can be used as 'conducting electrodes' required for touch screens, LCDs and organic LEDs. Which of the statements given above are correct?
Consider the following statements and select the correct answer from the code given below: 1. The presence of calcium sulphate makes water hard and unfit for use. 2. Diamond is harder than copper and iron. 3. The main component of air is oxygen. 4. Nitrogen is used in the manufacture of vanaspati ghee. Code:
What is heavy water (guru jal)?
The gas used in the manufacture of vanaspati ghee from vegetable oil is:
Which of the following does not contain carbon?
Which of the following catalysts is used for the hydrogenation of vegetable oils?