Science Write True or False

The zig-zag line separates the metals from nonmetals in the periodic table i.e. metals are on the left side and nonmetals are on the right side.

In a group, the metallic character decreases from top to bottom.

In a period, the metallic character increases from left to right.

In a period, atomic sizes increases from left to right.

All the elements of a group have the same number of valence electrons.

Lanthanides and actinides are also called the d-block elements.

The chemical properties of the elements in the same group show similarity.

Elements are classified on the basis of their atomic numbers.

There are 7 periods in the long form of the periodic table.

The d-block elements are called transition elements.

In the modern periodic table, properties of the elements are a periodic function of their atomic numbers.

Mendeleev was the first who successfully classified all known elements.

Mendeleev arranged elements in the increasing order of their atomic masses.

Mendeleev’s periodic table is more useful because it gives information about known and unknown elements.

Eka-aluminium was later named as germanium.

Newlands stated the law of triads.

Dobereiner stated the law of octet.

Dobereiner named the group of elements having similar properties as Triads.

Newlands was the first to classify elements having similar chemical properties into groups of three.

In an atom of an element, extra-nuclear electrons take part in the chemical reaction.

f-block elements are metalloids.

La stands for Lutetium.

Isotopes have similar chemical properties.

Isotopes have same atomic masses.

Tellurium, Polonium are metalloids.

Eka boron is known as Germanium.

Atomic number is the number of protons or electrons in the nucleus.

Eka-aluminium was discovered and named as gallium (Ga).

Metals are electronegative and non-metals are electropositive.

Upto Calcium, the law of octaves was found to be applicable.

The d-block elements are called transition elements

Argon is not an inert gas.

Group 1 elements in Modern Periodic table are referred as "alkali metals".

As we move from left to right in a period in Modern Periodic table, atomic size of the elements gradually increases.

Silicon is a metalloid.

Group 17 elements are known as Noble gases.

Periods are the horizontal rows of elements.

According to Mendeleev's periodic law, the properties of elements are a periodic function of their atomic numbers.

Lithium, Potassium and Sodium are elements forming Dobereiner's triad.