Answer : The correct option is A.
Explanation :
Metalloid : Metaloids are the elements whose properties lie between the metals and non-metals.
There are six commonly elements which are boron, silicon, germanium, arsenic, antimony and tellurium. The rare elements are polonium and astatine.
The relation between the group number and period number of metalloid is that the lower the group number, the lower the period numbers and the metalloids are found in a diagonal moving down from left to right in the periodic table.
7=cells
9= The Central Nervous system
10= not sure
Answer:
added water = 171 ml
Explanation:
Assuming volumes are additive, the rule that we will use to solve this question is:
M1V1 = M2V2
where:
M1 is the initial concentration = 0.4 m
V1 is the initial volume = 57 ml
M2 is the final concentration = 0.1 m
V2 is the final volume that we want to calculate
Substitute with the given in the above equation to get V2 as follows:
M1V1 = M2V2
(0.4)(57) = (0.1)V2
22.8 = 0.1V2
V2 = 228 ml
Now, the final volume is equal to the initial volume plus the amount of added water. So, to get the amount of added water, we will subtract the initial volume from the final volume as follows:
V2 = V1 + added water
228 = 57 + added water
added water = 228 - 57 = 171 ml
Hope this helps :)