**Answer:**

6 N

**Explanation:**

Force (Newtons) = mass (kg) times acceleration (m/s2)

2 kg x 3m/s2 = 6 kg/m/s2

**Explanation:**

The given chemical reaction will be as follows.

Also, mass deposited can be calculated using the formula as follows.

W = Zit

where, W = weight or mass of the substance

Z = electrochemical equivalent

i = current

t = time in seconds

Calculate value of Z for the given reaction as follows.

Z =

molar mass of Al = 26.98 g/mol

Z =

= g/mol

Therefore, putting the given values into the above formula as follows.

W = Zit

=

= 0.328 g

Thus, we ca conclude that **0.328 g of aluminium can be electroplated in the given situation.**

**Answer:**

30.25°C

**Explanation:**

The calorimeter is an equipment used to measure the combustion enthalpy of a substance. The heat loss in the reaction is used to heat the water and the equipment. By the conservation of energy:

Qcombustion + Qcalorimeter + Qwater = 0

Because there is no phase change:

Qcalorimeter = C*ΔT, where C is the heat capacity, and ΔT the variation in temperature (final - initial)

Qwater = m*c*ΔT, where m is the mass, and c is the specific heat (4.184 J/g°C).

The molar mass of lactose is 342.3 g/mol, so the number of moles in 2.50 g is:

n = mass/molar mass

n = 2.50/342.3

n = 0.0073 mol

Qcombustion = -5652 kJ/mol * 0.0073 mol

Qcombustion = -41.28 kJ

Qcombustion = - 41280 J

Thus,

-41280 + 1630*(T - 24.58) + 1350*4.184*(T - 24.58) = 0

(T - 24.58) * (1630 + 5648.4) = 41280

7278.4(T - 24.58) = 41280

T - 24.58 = 5.67

T = 30.25°C