Explanation:
Elements in the same group have same number of valence electrons. And we know, the elements which have same number of valence electrons, have similar physical and chemical properties. Hence, the elements in the same group have similar physical and chemical properties.
<u>Answer:</u> The correct answer is Option B.
<u>Explanation:</u>
Decomposition is a type of chemical reaction in which larger compound breaks down into two or more smaller compounds.
Double displacement reactions is defined as the chemical reaction in which exchange of ions takes place.
Synthesis reaction is a type of reaction in which two or more smaller compounds combines to form a single large compound.
Single displacement reaction is a type of reaction in which a more reactive metal displaces a less reactive metal from its chemical reaction.
In stomach, an acid is present known as hydrochloric acid and to neutralize its effect, antacid is taken which has 
as a component.
The reaction between HCl and 
is a type of neutralization reaction and it is a type of double displacement reaction.
The equation between the two follows:
Hence, the correct answer is Option B.
<h3>
1.</h3>
C) The volume of the gas is proportional to the number of moles of gas particles.
The Avogadro's law applies to ideal gases with constant pressure and temperature. By that law, the volume of an ideal gas is proportional to the number of moles of particles in that gas.
<h3>2.</h3>
B) The gas now occupies less volume, and the piston will move downward.
Boyle's Law applies to ideal gases with a constant temperature. The volume of an ideal gas is inversely related to its pressure. A high pressure drives gas particles together, such that they occupy less volume. The gas trapped inside the piston has a smaller volume. As a result, the the piston will move downward.
Alternatively, consider the forces acting on the piston. Both the atmosphere and gravity are dragging the piston down. In order for it to stay in place, the gas below it must exert a pressure to balance the two forces. Now the pressure from outside has increased. The gas inside needs to increase its pressure. It needs a smaller volume to create that extra pressure. As a result, its volume will decrease, and the piston will move downwards.
A) Head to tail joining of monomers. :) (confirmed correct answer, I took the test)
The speed and wavelength changes as a waves travels to a different depth. Slower and bigger amplitudes in shallower depths. Freq does not change
