Answer: Correct option is (D).
Explanation:
Given that unknown element has larger atomic radii than potassium atoms and its valence electrons feel an effective nuclear charge of +1 which means that this unknown element belongs to group(I) of the periodic table.
In periodic table:
- As we move down the group the value of ionization energy decreases down the group. This is due to increase in the size of an element.With increase in size valence electrons gets far away from the nucleus by which less energy will require to ionize the element.
- Electronegative characters also decreases when we move down the group.This is due to increase in size of an element by which electrons present in valence shells are far away from the nucleus.
So,It would have lower ionization energies than K and a lower electronegativity value than K.
<span>Organisms in biological ecosystems connect to one another through their need for matter as well as energy. Every organism needs molecules like proteins, carbohydrates, and fats to provide the raw building materials for their cells.</span>
At constant pressure a known moles of gas has volume which is directly proportional to temperature (Charle's Law)
Thus V α T
Therefore
V1/V2 = T1 /T2
V1 = initial volume = 10 L
T1 = initial temperature= 280 K
V2 = final volume = 20L
T2 = final temperature = ?
T2 = T1V2 / V1 = 280 X 20 / 10 = 560 K
Thus the new temperature will also doubles up as volume is increased by two times
The gram formula mass is another term for the mass of one mole of the substance which can be calculated by adding up the masses of the elements comprising the formula unit, molecules, etc.
a. Barium Fluoride (BaF2)
m = mass of Ba + 2(mass of F)
m = 137.327 g + 2(19 g)
m = 175.327 g
b. Strontium Cyanide (Sr(CN)2)
m = mass of Sr + 2(mass of C) + 2(mass of N)
m = 87.62 + 2(12) + 2(14)
m = 139.62 g
c. Sodium hydrogen Carbonate (NaHCO3)
m = mass of Na + mass of H + mass of C + 3(mass of O)
m = 23 + 1 + 12 + 3(16)
m = 84 g
d. Aluminum sulfide (Al2S3)
m = 2(mass of Al) + 3(mass of S)
m = 2(26.98) + 3(32)
m = 149.96 g