Answer:
a)Atomic number
Explanation:
Element symbol signifies the element. For eg, Na is sodium. Mass number is the sum of protons and neutrons of an atom of an element. Atomic mass is the molar mass of the given element. Finally, atomic number is unique to each element because it signifies the number of protons of that element. EACH ELEMENT has their UNIQUE number of protons. For eg, atomic number of hydrogen is 1 because it has 1 proton, NO OTHER ELEMENT HAS ATOMIC NUMBER 1 because NO OTHER ELEMENT HAS 1 proton.
Explanation:
has lost 1 electron. Therefore, a potassium ion has a smaller radius since it has less electrons.
Answer: Throughout the year, different parts of Earth receive the Sun's most direct rays. So, when the North Pole tilts toward the Sun, it's summer in the Northern Hemisphere. When the South Pole tilts toward the Sun, it's winter in the Northern Hemisphere.
It's impossible for it to be summer and winter in the same hemisphere because the southern and northern hemispheres have their seasons inverted. For example; when it is summer in the US it is winter in Australia.
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A solute dissolves in excess solvent to form a solution:
solute + solvent → solution
<h3>What is the Enthalpy and their relation ? </h3>
A thermodynamic system's enthalpy, which is one of its properties, is calculated by adding the system's internal energy to the product of its pressure and volume. It is a state function that is frequently employed in measurements of chemical, biological, and physical systems at constant pressure, which the sizable surrounding environment conveniently provides.
A solution is a uniform mixture of two or more components that can exist in the solid, liquid, or gas phases. The amount of heat that is released or absorbed during the dissolving process is known as the enthalpy change of solution (at constant pressure).
There are two possible values for this enthalpy of solution ( H solution ) : positive (endothermic) and negative (exothermic). It is most straightforward to visualize a hypothetical three-step process occurring between two substances while trying to grasp the enthalpy of solution. The solute is one substance; let's call it A. The solvent is the second component; let's call it B.
The initial procedure exclusively affects the solute A and calls for disabling all intramolecular forces holding it together. This indicates that the molecules of the solute separate. This process' enthalpy is known as H1. Since breaking interactions requires energy, this is always an endothermic process, hence H1>0.
Their sign will be opposite.
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