How many particles are there in 5.0 moles

3.01 × 10^24 particles

Explanation:

According to Avagadro, in one mole of a substance, there are 6.02 × 10^23 atoms or particles.

Using the formula: N = n × NA

Where;

N= number of particles or atoms

n = number of moles

NA = Avagadro's constant or number

This means that for 5 moles of a substance, there will be:

5 × 6.02 × 10^23

= 30.1 × 10^23

= 3.01 × 10^24 particles

answer: the enthalpy of the overall chemical reaction is +87.88 kj or +88 kj.

according to hess's law, the overall enthalpy of a reaction is the difference between the sum of enthalpy values of all the products and the sum of enthalpy values of all the reactants.

δh(reaction) = ∑nδh(products) - ∑nδh(reactants)

δh(reaction) = [δh +δh] - [δh]

δh(reaction) = [1(-287.02) + 1(0) ] - [1(-374.9)] kj = +87.88 kj

here, δh (pcl3) = -287.02 kj, δh(cl2) = 0, δh(pcl5) = -374.9 kj

therefore, enthalpy of the overall reaction is +87.88 kj or +88 kj.

"hydrogen bonding is the attraction of h atoms in the water molecule (slight + charge) to o atoms in a neighboring water molecule (slight - charge); it is a weak interatomic force. but it is still strong enough to the water molecules "stick" together."