There are 4 electron pairs (3 bonding and 1 lone pair) so the angle is 107 degrees. The 4 electron pairs are repelled to give a tetrahedral arrangement but the molecule has a pyrimidal shape due to the lone pair.
Answer:
Thermal expansion is the tendency of matter to change its shape, area, and volume in response to a change in temperature.
Explanation:
Energy is supplied to aluminium to raise the temperature of aluminium.
we can use the following equation to calculate the mass of aluminium
H = mcΔt
H - heat energy supplied
m - mass of material
c - specific heat capacity of aluminium
Δt - change in temperature - 35 °C - 15 °C = 20 °C
substituting the values in the equation
216 J = m x 0.90 J°C⁻¹g⁻¹ x 20 °C
m = 12 g
mass of aluminium is 12 g
