Answer:
The mass of a system does not change during a chemical reaction
Explanation:
Correct Answers
Answer:
that's because....
group 1 (e.g Na, K) those tend to lose one electron to gain noble gas electron configuration.
they can achieve that by just losing one electron from their outer shell.
as you go down the group 1, element gets bigger in size, which means there is more space between nucleus (which is in center of atom) and electron of outer shell. the more far away they are the less attraction force between them.
so its easier for potassuim to lose one electron than for lithuim.
so that means potassium will easily give up 1 electron to react with non metal or other element therefore it is more reactive than lithuim
but in case of non metal, the opposite happens but simple to understand.
as you go down the group 7 (halogen- Cl, Br, I) element will get bigger therefore force between nucleus and outer electron is getting smaller. they have to gain 1 electron in order to fill the outer shell (to gain noble gas electron configuration.)
as florine is more smaller in size than clorine it is more reactive because florine has more tendency to pull extra electron from metal or other element towards its side. so it easily gain 1 electron to react.
Answer:
Explanation:
The atomic radius of elements are used to estimate the sizes of elements. The atomic radius is taken as half of the inter-nuclear distance between two covalently bonded atoms of non-metallic elements or half of the distance between two nuclei in the solid state of metals.
To solve this problem we will obtain the atomic radius values of the given elements from a standard atomic radius table;
Si 111 pm
P 98 pm
Cl 79 pm
S 87pm
pm = picometer
We see that chlorine has the least atomic radius
Answer: Option (b) is the correct answer.
Explanation:
A synthesis reaction is the reaction in which two compounds or atoms combine together to result in the formation of a single compound.
For example, 
Thus, here CaO and 
combine together to result in the formation of calcium carbonate compound. Therefore, it is a synthesis reaction.
Therefore, we can conclude that the most likely products of Cao + co2 → CaCO3 reaction.
<h3><u>Answer;</u></h3>
D. It decreases and the pH increases.
<h3><u>Explanation;</u></h3>
- pH is a measure of the hydorgen ion concentration of a solution. Solutions with a high concentration of hydrogen ions have a low pH and solutions with a low concentrations of H+ ions have a high pH.
- <em><u>[H+] and [OH-] are inversely related. Therefore; As the concentration of H+ increases the pH decreases. Since the concentrations of H+ and OH- are inversely proportional, as one goes up, the other goes down. </u></em>
- <em><u>Therefore, an increase in OH- concentration will correspond to an increase in pH and a decrease in the concentration of H+.</u></em>
