CHEMISTRY HIGH SCHOOL

What is the Arrhenius definition of a base? A substance that increases H3O+ concentration when it is dissolved in water. A substance that increases OH– concentration when it is dissolved in water. A compound that donates protons. A compound that accepts protons

Answers

Answer 1

Answer:

Answer : The correct option is A substance that increases $OH^-$ concentration when it is dissolved in water.

Explanation :

Arrhenius Definitions :

Arrhenius Acid : It increases the concentration of hydronium ion $(H_3O^+)$ in an aqueous solution. In other words, a substance dissociates in water to form $H^+$ ion.

Arrhenius Base : It increases the concentration of hydroxide ion $(OH^-)$ in an aqueous solution. In other words, a substance dissociates in water to form $OH^-$ ion.

Answer 2

Answer:

Answer:

Explanation:

Related Questions

Why is a molecule of CO2 nonpolar even though the bonds between the carbon atom and the oxygen atoms are polar?(1) The shape of the CO2 molecule is symmetrical. (2) The shape of the CO2 molecule is asymmetrical. (3) The CO2 molecule has a deficiency of electrons. (4) The CO2 molecule has an excess of electrons.
Which substance will require more energy to heat if all the samples have the same mass and same temperature change?
What is true regarding methane and ammonia?
neon is a noble gases a very stable it does not readily combined with other elements which category does neon belong to
Which changes occur as a cadmium atom, Cd, becomes a cadmium ion, Cd2+?(1) The Cd atom gains two electrons and its radius decreases.(2) The Cd atom gains two electrons and its radius increases.(3) The Cd atom loses two electrons and its radius decreases.(4) The Cd atom loses two electrons and its radius increases.

Is a force created by the water that is displaced by an object.

Answers

Answer:

Buoyancy.

Explanation:

Buoyancy is a force created by the water that is displaced by an object. It is directly proportional to the amount of water that is being displaced by an object.

Hence, the greater the amount of water an object displaces; the greater is the force of buoyancy pushing the object up.

The buoyancy of an object is given by the formula;

$Fb = pgV\n\nBut, V = Ah\n\nHence, Fb = pgAh$

Where;

Fb = buoyant force of a liquid acting on an object.

g = acceleration due to gravity.

p = density of the liquid.

v = volume of the liquid displaced.

h = height of liquid (water) displaced by an object.

A = surface area of the floating object.

The unit of measurement for the buoyancy of an object is Newton (N).

Consider the reaction: 2 H2O (g)-->2 H2 (g) + O2 (g). ΔH=483.6 Kj/mol. If 2 moles of H2O (g) are converted H2(g) and O2(g) against a pressure of 1 atm at 125 degrees Celcius what is ΔE of reaction?

Answers

Answer : The value of $\Delta E$ of the reaction is, 480.29 KJ.

Explanation :

Formula used :

$\Delta E=\Delta H-\Delta n_g* RT$

where,

$\Delta E$ = internal energy of the reaction = ?

$\Delta H$ = enthalpy of the reaction = 483.6 KJ/mole = 483600 J

$\Delta n_g$ = change in the moles of the reaction = Moles of product - Moles of reactant = 3 - 2 = 1 mole

R = gas constant = 8.314 J/mole.K

T = temperature = $125^oC=273+125=398K$

Now put all the given values in the above formula, we get:

$\Delta E=483600J-(1mole* 8.314J/mole.K* 398K)$

$\Delta E=480291.028J$

$\Delta E=480.29KJ$

Therefore, the value of $\Delta E$ of the reaction is, 480.29 KJ.

dE = dH - PdV

2 H2O(g) → 2 H2(g) + O2(g)

You can see that there are 2 moles of gas in the reactants and 3 moles of gas in the products.

1 moles of ideal gas occupies the same volume as 1 mole of any other ideal gas under the same conditions of temp and pressure.

Since it is done under constant temp and pressure that means the volume change will be equal to the volume of 1 mole of gas

2 moles reacts to form 3 moles

The gas equation is

PV = nRT
P = pressure
V = volume (unknown)
n = moles (1)
R = gas constant = 8.314 J K^-1 mol^-1
- the gas constant is different for different units of temp and pressure (see wikki link) in this case temp and pressure are constant, and we want to put the result in an equation that has Joules in it, so we select 8.314 JK^-1mol^-1)
T = temp in Kelvin (kelvin = deg C + 273.15
So T = 403.15 K

Now, you can see that PV is on one side of the equation, and we are looking to put PdV in our dE equation. So we can say

dE = dH -dnRT (because PV = nRT)

Also, since the gas constant is in the unit of Joules, we need to convert dH to Joules

dH = 483.6 kJ/mol = 483600 Joules/mol

dE = 483600 J/mol - (1.0 mol x 8.314 J mol^-1K-1 x 403.15 K)
dE = 483600 J/mol - 3351.77 J
dE = 480248.23 J/mol
dE = 480.2 kJ/mol

tert-Butyl alcohol is a solvent with a Kf of 9.10 ∘C/m and a freezing point of 25.5 ∘C. When 0.807 g of an unknown colorless liquid was dissolved in 11.6 g of tert-butyl alcohol, the solution froze at 15.3 ∘C.Which of the following is most likely the identity of this unknown liquid?tert-Butyl alcohol is a solvent with a of 9.10 and a freezing point of 25.5 . When 0.807 of an unknown colorless liquid was dissolved in 11.6 of tert-butyl alcohol, the solution froze at 15.3 .Which of the following is most likely the identity of this unknown liquid?ethylene glycol (molar mass = 62.07 g/mol)1-octanol (molar mass = 130.22 g/mol)glycerol (molar mass = 92.09 g/mol)2-pentanone (molar mass = 86.13 g/mol)1-butanol (molar mass = 74.12 g/mol)

Answers

Answer: ethylene glycol (molar mass = 62.07 g/mol)

Explanation:

Depression in freezing point :

Formula used for lowering in freezing point is,

$\Delta T_f=k_f* m$

or,

$\Delta T_f=k_f* \frac{\text{mass of solute}}{\text{molar mass of solute}* \text{weight of solvent in kg}}$

where,

$T_f$ = change in freezing point

$k_f$ = freezing point constant= $9.10^0C/m$

m = molality

Given mass of solute = 0.807 g

Molar mass of solute=? g/mol

weight of solvent in kg= 11.6 g=0.0116 kg

$\Delta T_f=T^(o)_f-T_f=25.5^0C-15.3^0C)=10.2^0C$

$10.2=9.10* \frac{0.807}{\text{molar mass of solute}* 0.0116kg}$

${\text{molar mass of solute}}=62.07 g/mol$

Thus the solute is ethylene glycol which has same molecular mass as calculated, i.e 62.07 g/mol.

Which statement about a system at equilibrium is true?(1) The forward reaction rate is less than the reverse reaction rate.(2) The forward reaction rate is greater than the reverse reaction rate.(3) The forward reaction rate is equal to the reverse reaction rate.(4) The forward reaction rate stops and the reverse reaction rate continues.

Answers

Answer: Option (3) is the correct answer.

Explanation:

A reaction in which the concentration of reactants equal to the concentration of products is known as an equilibrium reaction.

For example, $Ca(OH)_(2)(s) + H_(2)O(l) \rightleftharpoons Ca^(2+)(aq) + 2OH^(-)(aq)$

Therefore, we can also say that in an equilibrium reaction rate of forward reaction becomes equal to the backward reaction.

The true statement about a system at equilibrium is that the forward reaction rate is equal to the reverse reaction rate.

What is equilibrium state?

Equilibrium state is that state in which the concentration of reactant as well as of producrs are constant. i.e. not changes.

Equilibrium state of any reaction will be represented by the double headed arrow as:

A + B ⇄ C + D

Given reaction defines that rate of forward reaction is equal to the rate of the backward reaction.

Hence option (3) is correct.

To know more about equilibrium state, visit he below link:

brainly.com/question/1495850

How many grams of lithium nitrate will be needed to make 250.0 grams of lithium sulfate?

Answers

the answer would be 313 g

in a collosion 15 kg object moving with a velocity of 3 m.s transfers all of its momentum to a 5 kg object. what would be the velocity of the 5 kg object after the collosion

Answers

P=mv
1st object- 45kg*m/s
45=5v
V=9m/s
The velocity if the second object is 9 meters per second

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