Answer:
Yes they are found in same period
Answer:
The average atomic mass is closer to Si- 28 because this isotope is present in more percentage in the sample.
Explanation:
Given data:
Atomic mass of silicon= ?
Percent abundance of Si-28 = 92.21%
Atomic mass of Si-28 = 27.98 amu
Percent abundance of Si-29 = 4.70%
Atomic mass of Si-29 = 28.98 amu
Percent abundance of Si-30 = 3.09%
Atomic mass of Si-30 = 29.97 amu
Solution:
Average atomic mass = (abundance of 1st isotope × its atomic mass) +(abundance of 2nd isotope × its atomic mass)+(abundance of 2nd isotope × its atomic mass) / 100
Average atomic mass = (92.21×27.98)+(4.70×28.98)+(3.09×29.97) /100
Average atomic mass = 2580.04 +136.21+92.61 / 100
Average atomic mass = 2808.86 / 100
Average atomic mass = 28.08amu.
The average atomic mass is closer to Si- 28 because this isotope is present in more percentage in the sample.
Answer:
NaH(s) + H2O(l) ------> NaOH(aq) + H2(g)
2Al(s) + 3Cl2(g) -----> 2AlCl3(s)
Explanation:
The rule of thumb in balancing chemical reaction equation is that the number of atoms of each element on the reactant side must be the same as the number of atoms of the same element on the product side. Only then can any reaction equation be seen as balanced.
For example there are two aluminum atoms on both sides of the reaction equation and six chlorine atoms on both sides of the reaction equation. Hence the reaction equation is balanced.
Answer:
The last one, to swim
Explanation:
The function of cilia and flagella move liquid past the surface of the cell. For single cells, such as sperm, this enables them to swim. For cells anchored in a tissue, like the epithelial cells lining our air passages, this moves liquid over the surface of the cell (e.g., driving particle-laden mucus toward the throat).
