HURRY ! Kumar is producing the photoelectric effect by using red light. He wants to increase the energy of emitted electrons. Ba
1 answer:
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The molecular weight of hemoglobin can be calculated using osmotic pressure
Osmotic pressure is a colligative property and it depends on molarity as
πV = nRT
where
π = osmotic pressure
V = volume = 1mL = 0.001 L
n = moles
R = gas constant = 0.0821 L atm / mol K
T = temperature = 25°C = 25 + 273 K = 298 K
Putting values we will get value of moles
we know that
Therefore
Answer: alkaline earth metals (group-IIA)
Explanation:
The element which donates the electron is known as electropositive element and forms a positively charged ion called as cation. The element which accepts the electrons is known as electronegative element and forms a negatively charged ion called as anion.
Alkaline earth metals donate 2 valence electrons to acquire noble gas configuration.
For example: Berrylium is the first alkaline earth metal with atomic number of 4 and thus has 4 electrons
Electronic configuration of berrylium:
Berrylium atom will loose two electrons to gain noble gas configuration and form berrylium cation with +2 charge.
Thus Elements donate 2 electron to produce a cation with a 2+ charge are alkaline earth metals.