GATE Questions

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An atom is the smallest particle of a substance. Chemical substances are divided into two major groups. They are

1. Pure Substances (and)

2. Mixtures.

There are two types of pure substances that are Elements and Compounds.

Elements : An element is a substance that is made up of only one kind of atoms and cannot be broken down into simpler substances by chemical means. Metals and Non- metals come under elements.

Examples of elements are Iron, Silver, Gold, Mercury etc.

Compounds : A Compound is a substance that is formed when two or more elements combine chemically.

Examples of compounds are Water, Carbon dioxide, methane, vinegar etc.

Mixtures : A Mixture is formed when two or more substances mixed together but not chemically combined.

Example: Air.

The micronutrients (or trace minerals): boron (B), chlorine (Cl), manganese (Mn), iron (Fe), zinc (Zn), copper (Cu), molybdenum (Mo), nickel (Ni). and cobalt (Co).

The sun moves around and in the house, but cannot touch the house.

We know that, elements in the same group of the periodic table have similar characteristics. Here magnesium and strontium are the same 2nd group elements and have same behavior. 

Therefore, strontium behaves same as magnesium. 

Gamma rays has the shortest wavelength and radio waves has the longest wavelength.

Microscopes are of three types. They are :

1) Optical microscopes

2) Electron microscopes

3) Scanning tunneling microscopes

Scanning tunneling microscopes are the microscopes that are used to view metal surfaces.

According to 2018 January reports, Mukesh Ambani is the first richest person in India being 18th in the world, followed by Azim Premji and S.P. Hinduja in second and third places.