Science-3 - Free MCQ Practice Test with solutions, CTET Science & Pedagogy

​Alkali metals have one electron in their outer shell so alkali metal can easily lose electrons. 

​Carbon Tetrachloride have no dipole moment because of regular tetrahedral structure. 

​Bupropion is used to treat major depressive disorder and to help people stop smoking.

​For oxygen, a molecule consists of two oxygen atoms, and has a weight of 2 x 16 = 32. For carbon dioxide, there is one carbon atom (weight 12) and two oxygen atoms (mass 16 x 2) for a total of 44. This means that carbon dioxide should be about 44/32 = 1.375 times (ideally) as heavy as an equivalent volume of oxygen. In reality, carbon dioxide is 1.383 times as heavy as oxygen.Even after solidification carbon di oxide is slightly heavier than similar volume of solid oxygen.

The acid produced by ants is called formic acid.The name comes from the Latin word for ant, which is “formica.” Chemically, it is a simple carboxylic acid. 

In semiconductor physics, a donor is a dopant atom that, when added to a semiconductor, can form a n-type region. All except aluminium are donor atom. 

​0 K is equivalent to – 273°C. 

​Carbon gives hardness to Stainless Steel. 

Lead Sulphate is not soluble in water. 

​The main constituent of biogas is methane. Biogas comprises primarily methane (CH₄) and carbon dioxide (CO₂) and may have small amounts of H₂S,H₂0 (moisture) . 

​The pH of human blood is between 7.35 to 7.45. 

This theory was given by Willard Frank Libby in 1949. To determine the age of wood and bones (the time which elapsed after the death of plant) is called Ratio Carbon Dating. The Half-life of Carbon 14 is 5,730 + 40 years. 

• Silver iodide is used for artificial rain, not horn silver.
• Silver chloride is not used for artificial rain.
• Zinc phosphide is indeed a commonly used rat poison.
• Zinc oxide, not zinc sulphide, is known as philosopher’s wool.

​Neutron is a neutral particle which has no electrical charge. It was discovered by Chadwick in 1932. 

​Nitrogen gas is used in the tyres of an aeroplane. This is because the nitrogen gas does not support combustion and can assist in preventing wheel fire when the aircraft lands . 

​Coal minerals are divided mainly into four types on the basis of the percentage of Carbon amount- Peat, Lignite, Bituminous and Anthracite. 

​It is an extension of the older carat (Karat in North American spelling) system of denoting the purity of gold by fractions of 24, such as ’18 carat’ for an alloy with 75% (18 parts per 24) pure gold by mass. 

​Radioactivity was discovered in 1896 by the French Scientist Henri Becquerel when he was working with phosphorescent materials. 

​The element found the maximum in the soil layer is Oxygen 46.8% followed by Silicon 27.2%, Calcium 3.65% and Carbon 0.6%.