1- Compared to the charge of proton the electron charge is 2- the gold foil discovery led to the discovery of

3- which particles are found in nucleus

4- a vertical column in the periodic table are known as

5- the horizontal row on the periodic table are

Explanation:

1- Compared to the charge of proton the electron charge is  negatively charged

An electron is a negatively charged subatomic particle which usually orbits the nucleus in discrete energy levels

2- the gold foil discovery led to the discovery of  the nucleus

Ernst Rutherford performed the gold foil experiment where he suggest the atomic model of the atom. Here an atom is made up of small positively charged center where nearly all the mass is concentrated.

3- which particles are found in nucleus Protons and Neutrons

The nucleus of an atom is the center of the atom. It is here that the mass of an atom is concentrated. This is because the more massive subatomic particles of protons and neutrons are found here.

4- a vertical column in the periodic table are known as Group or family

The vertical column on the periodic table is known as the group. Down a group the energy level increases and the atoms becomes bigger.

5- the horizontal row on the periodic table are the Period

The horizontal column on the periodic table is the period.

answer: enthalpy

explanation:

for a exothermic reaction, the energy is released i.e. the energy of the products is lower than the energy of the reactants.

= enthaply

= energy of products

= energy of reactants

as , thus comes out to be negative. negative value of enthalpy shows that the reaction is exothermic.

tracks, burrows, eggshells, nests, tooth marks, or gastroliths