Reaction of sodium with water
Sodium metal reacts rapidly with water to form a colourless solution of sodium hydroxide (NaOH) and hydrogen gas (H2). The resulting solution is basic because of the dissolved hydroxide. The reaction is exothermic. During the reaction, the sodium metal may well become so hot that it catches fire and burns with a characteristic orange colour. The reaction is slower than that of potassium (immediately below sodium in the periodic table), but faster than that of lithium (immediately above sodium in the periodic table).
2Na(s) + 2H2O → 2NaOH(aq) + H2(g)
Answer:
C
Explanation:
Metals are good conductors of heat
Answer:
SiF4 is not a polar covalent bond.
Explanation:
SiF4 is a nonpolar molecule because the fluorine's are arranged around the central silicon atom in a tetrahedral molecule with all of the regions of negative charge cancelling each other out.
Answer:
Choice d. No effect will be observed as long as other factors (temperature, in particular) are unchanged.
Explanation:
The equilibrium constant of a reaction does not depend on the pressure. For this particular reaction, the equilibrium quotient is:
.
Note that the two sides of this balanced equation contain an equal number of gaseous particles. Indeed, both and will increase if the pressure is increased through compression. However, because and have the same coefficients in the equation, their concentrations are raised to the same power in the equilibrium quotient .
As a result, the increase in pressure will have no impact on the value of . If the system was already at equilibrium, it will continue to be at an equilibrium even after the change to its pressure. Therefore, no overall effect on the equilibrium position should be visible.
Answer : The pressure of hydrogen gas is, 739.3 torr
Explanation :
As we are given:
Vapor pressure of water = 18.7 torr
Barometric pressure = 758 torr
Now we have to calculate the pressure of hydrogen gas.
Pressure of hydrogen gas = Barometric pressure - Vapor pressure of water
Pressure of hydrogen gas = 758 torr - 18.7 torr
Pressure of hydrogen gas = 739.3 torr
Therefore, the pressure of hydrogen gas is, 739.3 torr