What happens when a catalyst is used in a chemical reaction?

The overall effect of a catalyst to the reaction is that it lowers the activation energy of a chemical reaction. Catalyst is a substance that speeds a chemical reaction. It is not consumed as the reaction proceeds. A catalyst offers a new route for faster reaction. 

Explanation:

A catalyst is a specie which makes the rate of reaction faster without itself getting consumed into the chemical reaction.

A catalyst decrease the activation energy barrier for the chemical reaction so that, reactant molecules with low energy can easily participate into the reaction.

Hence, product formation becomes faster.

Therefore, overall effect of adding a catalyst will have an increase in formation of products.

Answer: Non covalent interactions.

Explanation: The non covalent interactions can be defined as the interaction among molecules based on the variation among the electromagnetic radiations.

These molecules are not attached to each other based on the sharing of the electrons.

These interactions are Van der Waals, electrostatic, hydrophobic interactions.

The interaction among the molecules is important in order to maintain the three dimensional structure of compound such as carbohydrates and protein molecules.

Colligative properties depend on the amount of solute dissolved in a solvent. These set of properties do not depend on the type of species present. These properties include freezing point depression, boiling point elevation, osmotic pressure and vapor pressure lowering. The correct answer is the last option. The solution which has the highest amount of solute or the 2.0 m NaCl solution will have lower freezing point than the other given choices.

Answer: 2.0 M NaCl

Explanation: :)

Answer:

Sodium is a silvery-white metal that reacts with chlorine gas, which is a yellow-greenish gas that is toxic. The  reaction gives off a lot of heat. After the reaction, which statement is true about the chemical properties of the product, sodium chloride?

Pure sodium reacts violently and sometimes explosively with water producing sodium hydroxide, hydrogen gas and heat

2Na(s) + 2H2O(l) → 2NaOH(aq) + H2(g)

Chlorine is a very poisonous yellow green gas with a sharp odour that was used in gas warfare during WW1

Sodium and chlorine reacts with each other, however, to produce one of the most familiar substance used in cooking and preservation industry today Sodium Chloride or Common salt or table salt in the irreversible equation;

2Na(s) + Cl2(g) → 2NaCl(s)

Explanation:

It is easy to see why this reaction takes place so readily sodium has one electron in its outermost valence shell while chlorine has seven electrons in its valence shell. when sodium atom transfers one electron to chlorine atom forming a sodium cation (Na+) and a chloride anion (Cl-) both ions have complete valence shells and are energetically more stable. the reaction is extremely exothermic, producing a bright yellow light and a great deal of heat and fumes of sodium chloride.

In a reaction observation of the reaction process you will see sodium flares up almost immediately upon reaction with water.

Answer:

mass of acetone added:

w acetone = 21.676 g

Explanation:

decrease in vapor pressure:

• ΔP = - (P*a)(Xb,l)

∴ ΔP = - 1.576 KPa = Pa - P*a

∴ a: water (solvent)

∴ b: C3H6O (solute)

∴ P*a (65°C) = 25.022 KPa

⇒ ΔP/(- P*a) = Xb,l

⇒ Xb.l = - 1.576 KPa/(- 25.022 KPa) = 0.063

∴ Xb = nb/nt = nb/(na + nb) = (wb/Mb)/[(wa/Ma) + (wb/Mb)]

∴ Mb = 58.08 g/mol (molar mass acetone)

∴ Ma = 18.015 g/mol (molar mass water)

∴ wa = 100 g

⇒ 0.063 = (wb/58.08)/[(100/18.015) + (wb/58.08)]

⇒ (0.063)[(5.55 + (wb/58.08)] = wb/58.08

⇒ 0.3497 + 1.085 E-3wb = wb/58.08

⇒ 20.3106 + 0.063wb = wb

⇒ 20.3106 = wb - 0.063wb

⇒ 20.3106 = 0.937wb

⇒ 20.3106/0.937 = wb

⇒ 21.676 g = wb

Answer:

By measuring it's Radical velocity using Doppler Phenomenon...

Explanation:

It is done by measuring the absorption spectrum produces by a star as a result of measuring Doppler's relative wavelength. The star with the lower speed must have lower absorption spectrum extent as compared to the faster one.

Answer:

mm = 78.329 g/mol

Explanation:

osmotic pressure (π):

• π = Cb*R*T

∴ a: water (solvent)

∴ b: solute nonelectrolytic

∴ Cb [=] mol/L

∴ π = (2.49E2 torr)*(atm/760 torr) = 0.3276 atm

∴ wb = 0.314 g

∴ T = 21.0°C = 294 K

∴ R = 0.082 atm.L/K.mol

∴ molar mass [=] g/mol

⇒ Cb = π/RT

⇒ Cb = (0.3276 atm)/[(0.082 atm.L/K.mol)(294 K)]

⇒ Cb = 0.0136 mol/L

⇒ moles solute (nb) = (0.0136 mol/L)*(2.95E2 mL)*(L/1000 mL)

⇒ nb = 4.01 E-3 mol

∴ molar mass (mm):

⇒ mm = (0.314 g)/(4.01 E-3 mol)

⇒ mm = 78.329 g/mol

The freezing point depression is -1.3 °C for a solution of 35.9 g of a 3.3 × 10² g/mol solute in 150.0 g of water.

What is the freezing point depression?

Freezing point depression (ΔT) is a colligative property observed in solutions that results from the introduction of solute molecules to a solvent.

The freezing points of solutions are all lower than that of the pure solvent and are directly proportional to the molality of the solute.

ΔT = i × Kf × m

m = ΔT / i × Kf

m = (1.3 °C) / 1 × (1.86 °C/m) = 0.70 m

where,

• i is the van 't Hoff factor (1 for nonelectrolytes).
• Kf is the cryoscopic constant (1.86 °C/m for water).
• m is the molality of the solution.

Since the 0.70 m solution has 150.0 g (0.1500 kg) of water, we will use the definition of molality to calculate the moles of solute.

m = moles of solute / kg of solvent

moles of solute = m × kg of solvent = 0.70 mol/kg × 0.1500 kg = 0.11 mol

0.11 moles of solute have a mass of 35.9 g. The molar mass of the solute is:

M = 35.9 g/0.11 mol = 3.3 × 10² g/mol

The freezing point depression is -1.3 °C for a solution of 35.9 g of a 3.3 × 10² g/mol solute in 150.0 g of water.

Learn more about freezing point depression here: brainly.com/question/14115775

Answer:

molr mass (mm):

mm = 342.43 g/mol

Explanation:

freezing point (ΔTf):

• ΔTf = - Kf*mb

∴ ΔTf = - 1.3°C

∴ a: water (solvent)

∴ b: solute

∴ mb: molality of the solute [=] mol/Kg

∴ Kf: cryoscopic constant

⇒ Kf water = 1.86 °C.Kg/mol

∴ wb = 35.9 g

∴ wa = 150.0 g = 0.150 Kg

∴ molar mass solute (mm) [=] g/mol

⇒ mb = - ΔTf/Kf

⇒ mb = - ( - 1.3°C)/(1.86 °CKg/mol)

⇒ mb = 0.6989 mol/Kg

∴ moles solute (nb):

⇒ nb = (0.6989 mol/Kg)(0.150 Kg) = 0.1048 mol

molar mass:

⇒ mm = (35.9 g)/(0.1048 mol) = 342.43 g/mol

Answer:

Endothermic reaction chemical equation

Reactnt A + Reactant B + Heat (energy) ⇒ Products

Exothermic reaction chemical equation

Reactnt A + Reactant B ⇒ Products + Heat (energy)

Explanation:

Endothermic Reaction

An endothermic reaction is a reaction that reaction that requires heat before it would take place resulting in the absorption of heat from the surrounding that can be sensed by the coolness of the reacting system

An example of an endothermic reaction is a chemical cold pack that becomes cold when the chemical and water inside it reacts

Exothermic Reaction

An exothermic reaction is one that rekeases energy to the surroundings when it takes place. This is as a result of the fact that the combined heat energy of the reactants is more than the chemical heat energy of the products. An example of an exothermic reaction is a burning candle