How much water should be added to 4.3 moles of LiBr to prepare a 2.05 m solution?

2.1 kg of water

Explanation:

Step 1: Given data

Moles of lithium bromide (solute): 4.3 molesMolality of the solution (m): 2.05 m (2.05 mol/kg)Mass of water (solvent): ?

Step 2: Calculate the mass of water required

Molality is equal to the moles of solute divided by the kilograms of solvent.

m = moles of solute/kilograms of solvent

kilograms of solvent = moles of solute/m

kilograms of solvent = 4.3 mol /(2.05 mol/kg) = 2.1 kg

According to arrhenius theory of acid and bases, an acid is a proton donor, while base donates hydroxyl ions. further, acid and base reacts to form salt and water.consider following example.hcl    +      h2o          →      cl-          +      h3o+here, hcl has donated a proton, hence it is an acid.now consider following reactionhcl      +      naoh            ↔      nacl      +        h2oin this reaction, hcl donates proton, hence it is acid. on other hand, naoh donates hydroxyl ion (i.e. hence it is a base.   

Descriptive investigations are mainly questions to uncover information. it does not have an hypothesis. it's mainly gathering information, it is not repeatable as you are just asking questions.