Answer:
Option A) Na
Explanation:
From the options given above, sodium (Na) is most likely to lose electron to form ion
Na is a group 1 metal. Metals form ions by losing electron(s).
From the options given above, only Na is a metal and so it is most likely to form ion by losing electron
Physical change there is no energy lost or gain. Basically the physical change is the change of state like melting
Electrons in an atom are held there by the force of attraction exerted by the positive charge of the nucleus on the negative charge of the electron. Energy is required to remove an electron from atom to overcome this attractive force.
Answer:
the mass of CaO present at equilibrium is, 0.01652g
Explanation:
= 3.8×10⁻²
Now we have to calculate the moles of CO₂
Using ideal gas equation,
PV =nRT
P = pressure of gas = 3.8×10⁻²
T = temperature of gas = 1000 K
V = volume of gas = 0.638 L
n = number of moles of gas = ?
R = gas constant = 0.0821 L.atm/mole.k

Now we have to calculate the mass of CaO
mass = 2.95 * 10 ⁻⁴ × 56
= 0.01652g
Therefore,
the mass of CaO present at equilibrium is, 0.01652g
They have high melting and boiling points and are hard and brittle