Element | MCQs

Explanation

Mercury is the only metal that is liquid at normal temperatures. 

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Chemical compounds of mercury have found uses in batteries, in biocides in the paper industry, in paints, and on seed grain, as antiseptics in pharmaceuticals, as reagents in laboratories, and as catalysts.

Four other elements are liquids slightly warmer than room temperature.

They are:

• francium
• cesium
• gallium
•  rubidium

ND31-12-2022

SH10-8-2023

Explanation

Symbol: Hg

Atomic number: 80

Melting point: -38.83 °C

Atomic mass: 200.59 u

Explanation

Sodium is a chemical element with the symbol Na and atomic number 11.

It is a soft, silvery-white, highly reactive metal.

Sodium is an alkali metal, being in group 1 of the periodic table.

Explanation

The elements of the periodic table sorted by atomic number

Atomic number Name chemical element                 Symbol

1                         Hydrogen                                             H

2                         Helium                                                     He

3                         Lithium                                                      Li

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RY 15-01-2023

Explanation

Explanation

Henry Cavendish - He discovered hydrogen gas and the composition of water contains two parts of hydrogen and one part of oxygen.

Symbol: H

Atomic mass: 1.00784 u

Atomic number: 1

Named by: Antoine Lavoisier (1783)

Explanation

Explanation

In the modern periodic table, there are 7 periods (horizontal rows) and 18 groups (vertical columns).

Explanation

Silicon is a chemical element with the symbol Si and atomic number 14.

Silicon dioxide (SiO₂) is the primary component in glass, making it transparent and durable.

It is obtained from sand (quartz).

It is essential in glass manufacturing

Explanation

Fluorine is the most electronegative element on the periodic table.

Fluorine is the most electronegative element because it has 5 electrons in its 2p shell.

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