Which statements describe Rutherford’s model of the atom? Select all that apply.

Quinine is an important type of molecule that is involved in photosynthesis. The transport of electrons mediated by quinone in c

Irina18 [472]

Answer:

The heat of combustion is -25 kJ/g = -2700 kJ/mol.

Explanation:

According to the Law of conservation of energy, the sum of the heat released by the combustion reaction and the heat absorbed by the bomb calorimeter is equal to zero.

Qcomb + Qcal = 0

Qcomb = - Qcal

The heat absorbed by the calorimeter can be calculated with the following expression.

Qcal = C × ΔT

where,

C is the heat capacity of the calorimeter

ΔT is the change in temperature

Then,

Qcomb = - Qcal

Qcomb = - C × ΔT

Qcomb = - 1.56 kJ/°C × 3.2°C = -5.0 kJ

Since this is the heat released when 0.1964 g o quinone burns, the energy of combustion per gram is:

$\frac{-5.0kJ}{0.1964g} =-25kJ/g$

The molar mass of quinone (C₆H₄O₂) is 108 g/mol. Then, the energy of combustion per mole is:

$\frac{-25kJ}{g} .\frac{108g}{1mol} =-2700kJ/mol$

6 0

3 years ago

Write formulas and names for two binary molecular compounds

lyudmila [28]

Answer:

NaCl sodium chloride

HF hydrogen flouride

Explanation:

7 0

3 years ago

How many copper atoms are in 150 g of copper metal

GaryK [48]

1. From grams -> mole:

=grams given x 1 mol/molar mass

So 150 g Cu x 1 mol Cu/63.546 g Cu = 2.4 mol Cu

2. From mole -> atoms

=number of mol x 6.022x10^22 atoms/1 mol

So 2.4 mol Cu x 6.022x10^22 atoms Cu/1 mol Cu = 1.4 x 10^24 atoms Cu

5 0

3 years ago

What is the ground-state electron configuration of a neutral atom of manganese?.

Alchen [17]

Explanation:

elctronic configuration of manganese

Mn=1s²2s²2p⁶3s²3p⁶4s²3d⁵

ground state

Mn=Ar3d⁵4s²

note that Ar is argon

3 0

3 years ago

Read the given equation. 2Na + 2H2O ? 2NaOH + H2 During a laboratory experiment, a certain quantity of sodium metal reacted with

emmasim [6.3K]

Answer:

The number of moles of Na metal that used initially = 0.70 mol.

The quantity of Na metal used initially to produce 7.80 of H₂ gas = 16.02 g.

Explanation:

It is a stichiometry problem.

2Na + 2H₂O → 2NaOH + H₂,

The balanced equation shows that 2.0 moles of Na metal react with 2.0 moles of water to produce 2.0 moles of NaOH and 1.0 mole of H₂,

Firstly, we need to convert the volume of H₂ (7.80 L) produced to no. of moles (n) using the ideal gas law: PV = nRT,

where, P is the pressure of the gas in atm (P at STP = 1.0 atm),

V is the volume of the gas in L (V = 7.80 L),

n is the number of moles in mole,

R is the general gas constant (R = 0.082 L.atm/mol),

T is the temperature of the gas in K (T at STP = 0.0 °C + 273 = 273.0 K).

∴ The number of moles of H₂ gas (n) = PV / RT = [(1.0 atm)(7.80 L)] / [(0.082 L.atm/mol.K)(273.0 K)] = 0.35 mol.

Using cross multiplication:

2.0 moles of Na will produce → 1.0 mole of H₂, from the stichiometrey.

??? moles of Na will produce → 0.35 mole of H₂.

∴ The number of moles of Na metal that used initially = (2.0 mol)(0.35 mol) / (1.0 mol) = 0.70 mol.

Now, we can get the quantity of Na metal using the relation:

∴ mass = n x molar mass = (0.70 mol)(22.989 g/mol) = 16.02 g.

6 0

3 years ago