Answer:
The element with electron configuration 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^5 is manganese (25Mn).
Explanation:
Step 1: Data given
The element with electron configuration 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^5
has 25 electrons.
This element has 2 electrons on the first shell, 8 electrons on the second shell, 13 electrons on the third shell and 2 electrons on the outer shell (valence electrons).
This means this element is part of group VII.
The element with 25 electrons, we can find on the periodic table, with atomic number 25.
The element with electron configuration 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^5 is manganese (25Mn).
O2=32 g/ mol
1.15/32=0.035
N2=28 g/mol
1.55/28=0.055
in STP every 22.4 litters is 1 mol
Answer:
1. n = 0.174mol
2. T= 26.8K
3. P = 1.02atm
4. V = 126.88L
Explanation:
1. P= 2.61atm
V = 1.69L
T = 36.1 °C = 36.1 + 273= 309.1K
R = 0.082atm.L/mol /K
n =?
n = PV / RT = (2.61x1.69)/(0.082x309.1)
n = 0.174mol
2. P = 302 kPa = 302000Pa
101325Pa = 1atm
302000Pa = 302000/101325 = 2.98atm
V = 2382 mL = 2.382L
T =?
n = 3.23 mol
R = 0.082atm.L/mol /K
T= PV /nR = (2.98x2.382)/(3.23x0.082) = 26.8K
3. P =?
V = 0.0250 m³ = 25L
T = 288K
n = 1.08mol
R = 0.082atm.L/mol /K
P = nRT/V = (1.08x0.082x288)/25 = 1.02atm
4. P = 782 torr
760Torr = 1 atm
782 torr = 782/760 = 1.03atm
V =?
T = 303K
n = 5.26 mol
R = 0.082atm.L/mol /K
V = nRT/P
V = (5.26x0.082x303)/1.03 = 126.88L
Metals are the type of elements that are most likely to form more than one type of ion, for instance iron can form the ion of Fe^2+ or Fe^3+.
Answer:
No
Explanation:
The pH scale is a scale graduated from 0-14 which shows the degree of acidity of alkalinity of a substance. The pH scale is graduated in such a way that 0-6.9 indicates acidity, 7.0 indicate a neutral substance, while a pH of 8-14 indicates alkalinity respectively.
There are three main definitions of acids/bases
- Arrhenius definition
-Brownstead-Lowry definition
-Lewis definition
Arrhenius explains acids as any substance that produces hydrogen ions as its only positive ion in solution while a base produces hydroxide ions as its only negative ion in solution. The pH scale is based on corresponding values of pH derived from aqueous solutions of these substances.
However, not all acids/bases produces hydrogen or hydroxide ions in solution. Brownstead-Lowry definition of acids and Lewis definition of acids could be extended to nonaqueous media where the pH can not be measured as there are no hydrogen or hydroxide ions present in the solution.
This implies that pH measurement may not apply to acids/bases in the all the categories of acids/bases hence it can not be utilized for all acids and bases.
Arrhenius - sodium carbonate
Brownstead-Lowry - concentrated HF
Lewis acid - AlCl3