Atoms try to have the same number of protrons and electrons. True or false

Write a balenced chemical equation for the reaction: include abbreviation for the physical states-

WITCHER [35]

Answer:

MgBr(aq) + (NH4)3PO4(aq) -------> NH4Br(aq) + Mg3(PO4)2(s)

Explanation:

4 0

3 years ago

Consider the reaction between a solution of molecule A and a solid block of molecule B. In general, for a reaction to occur, the

Blababa [14]

Answer:

Decreasing the volume of solvent in the solution of molecule A

Explanation:

We know that one of the factors that affect the rate of reaction is the concentration of the reactants. The greater the concentration of reactants, the faster the rate of reaction (the greater the frequency of collision between reactants).

Hence, when we decrease the volume of solvent in the solution of molecule A, the concentration of the solution increases and consequently more particles of molecule A are available to collide with particles of molecule B resulting in a higher rate of reaction.

3 0

2 years ago

When a 0.245-g sample of benzoic acid is combusted in a bomb calorimeter, the temperature rises 1.643 ∘C . When a 0.260-g sample

sveticcg [70]

Answer:

The heat of combustion per moles of caffeine is 4220 kJ/mol

Explanation:

Step 1: Data given

⇒ When benzoic acid sample of 0.245 grams is burned the temperature rise is 1.643 °C

⇒ When 0.260 gram of caffeine is burned, the temperature rise is 1.436 °C

⇒ Heat of combustion of benzoic acid = 26.38 kJ/g

Step 2: Calculate the heat released: for combustion of benzoic acid

0.245 g benzoic acid * 26.38 kJ/g = 6.4631 kJ

Step 3: Calculate the heat capacity of the calorimeter:

c = Q/ΔT

Q = 6.4631 kJ / 1.643°C = 3.934 kJ/ °C

Step 4: Calculate moles of a 0.260 g sample of caffeine:

Moles caffeine = Mass caffeine / Molar mass caffeine

0.260 grams/ 194.19 g/mol = 0.0013389 moles

Step 5: Calculate heat released: for combustion of caffeine

Q = c * ΔT

Q = 3.934 kJ/°C * 1.436 °C = 5.65 kJ

Step 6: Calculate the heat of combustion per mole of caffeine

5.65 kJ / 0.0013389 moles = 4219.9 kJ/mol ≈ 4220 kJ/mol

The heat of combustion per moles of caffeine is 4220 kJ/mol

4 0

3 years ago

If 25.5g of sodium thiosulphate was dissolved in 40g of distilled water at 25°C,

zhenek [66]

Answer:

Formula: Na2S2O3

we get solubility.

Divide the mass of the compound by the mass of the solvent and then multiply by 100 g to calculate the solubility in g/100g .

Solution given:

mass of sodium thiosulphate [m1]=25.5g

mass of water [m2]=40g

at temperature [t]=25°C

we have

solubility in g/dm^3 : $\frac{solute in gram}{solvent in gram} *100$

= $\frac{25.5}{40}*100$
=63.75g /litre=63.75g/dm³

solubility in g/dm^3 :63.75g/dm³

now

solubility of the solute in mol/dm^3=:63.75g/dm³/178=0.4 mol/dm³

6 0

2 years ago

Hydrogen chloride, HCl, is classified as an Arrhenius acid because it produces(1) H+ ions in aqueous solution(2) Cl– ions in aqu

frozen [14]

Answer is (1) Produces H+ in aqueous solution

8 0

3 years ago