Answer: D : A is 3 : 2.
Explanation:
The law of definite proportion is being used here. The law states that a given compound always has the same proportion of its constituent elements by mass.
2a + b = c + 3d
This actually means that, two moles of “a” react with a mole of “b” to produce a mole of “c” and 3 moles of “d”
Using the concept of stoichiometry coefficients of d and a
d:a = 3:2
Generally bonds present between molecules are called intermolecular forces. they are three types:
1) Wander Wall forces (London forces)
2) Dipole - dipole interaction.
3) Hydrogen bond.
- As molecular weight increases boiling point also increases due to surface are is directly proportional to Wander Waal forces.
- Dipole-dipole attraction: the attraction between two different polarizable molecules is called dipole- dipole attraction, this attraction play important role in boiling point.
- Hydrogen bond: electrostatic attraction between hydrogen and more electronegative atom is called hydrogen bond.
- The substance which has hydrogen bond have higher boiling point.
1-pentanol has hydrogen bond
1- Bromopentane has dipole - dipole
1-pentene has only London forces
Hydrogen bond > dipole - dipole attraction > London force
V ( NaOH ) = 25 mL in liters : 25 / 1000 => 0.025 L
M ( NaOH ) = 0.160 M
V ( H2SO4) = 17 mL / 1000 => 0.017 L
M ( H2SO4) = ?
number of moles NaOH:
n = M x V = 0.160 x 0.025 => 0.004 moles NaOH
Mole ratio :
<span>2 NaOH + H2SO4 = Na2SO4 + 2 H2O
</span>
2 moles NaOH ----------- 1 mole H2SO4
0.004 moles NaOH ----- ? moles H2SO4
moles H2SO4 = 0.004 x 1 / 2
= 0.002 moles of H2SO4
M ( H2SO4) = n / V
M = 0.002 / 0.017
= 0.117 M H2SO4
Answer B
hope this helps!