Answer:
1 valence - Alkali Metals: Li Lithium, Na Sodium, K Potassium
2 valence - Alkaline Earth Metals: Be Beryllium, Mg Magnesium, Ca Calcium
3 valence - Non-metals: B Boron, Al Aluminium
4 valence - Non-metals: C Carbon, Si Silicon
5 valence - Non-metals: N Nitrogen, P Phosphorus
6 valence - Non-metals: O Oxygen, S Sulfur, Se Selenium
7 valence - Halogens: F Fluorine, Cl Chlorine, Br Bromine
8 valence - Noble Gases: He Helium, Ne Neon, Ar Argon
In this reaction, water acts as the base and donates a proton to hydrazine (H2NNH2). Hydrazine becomes protonated: [N2H5]<span>+ And thus hydrazine in this reaction is actually a base. The conjugate base of the acting acid H2O is OH- (hydroxide ion).</span>
7.20594 x 10^20
First you must determine how many moles of P3O5 you have. This is done by using the formula
Number of moles (n) = mass in grams of substance (m) /divided by/ Molar mass (M) [this is the sum of the atomic mass of all atoms in the compound]
n = 0.170 / P (31 x 2) + O (16 x 5)
n = 0.170 / 142
n = 0.001197 moles
Then you use avagadros number 6.02 x10^23 this is the number of atoms in one mole of any substance. Since you have 0.001197 moles you multiply the number of moles by avagadros number
0.001197 x (6.02 x 10^23)
= 7.20594 x 10^20 atoms
Answer:
c. ₆¹²C and ₆¹³C
Explanation:
Properly writing the given options:
a. ₁¹H and ₁¹H⁺
b. ₇¹⁴N and ₇¹⁴N³⁻
c. ₆¹²C and ₆¹³C
Electrons are the crux of chemical reactions. These negatively charged subatomic particles determines chemical properties of atoms and how they combine with other atoms.
Atoms having the same number of electrons especially in their valence shells shares similar chemical properties.
From the problem above, we have been given some information about the atom.
The mass number is given by the superscript before the symbol of the atom and it signifies the sum of the number of protons and neutrons in the atom.
The atomic number is shown by the subscript and it denotes the number of protons in the atom.
For neutral atoms that has not lost or gained any additional electron, the atomic number is the same as the number of electrons.
The superscript after the atom is the charge on the particle. It represents the number of electrons lost or gained by the atom.
In {c. ₆¹²C and ₆¹³C}, the atom is in a neutral state. Here the atomic number which is 6 is the number of protons in the atom. This is also the number of electrons in the atom. Therefore, the two atoms would have similar chemical properties and behavior.
This is not so for the others as their number electrons are different.
