Two scientists were competing to earn some grant money to fund their research, because

If 3 moles of a compound use 12 J of energy in a reaction, what is the Hreaction in kJ/mol

igomit [66]

Answer:

$\Delta _RH=4x10^{-3}\frac{kJ}{mol}$

Explanation:

Hello,

In this case, the molar enthalpy of reaction is obtained by dividing the involved energy by the reacting moles:

$\Delta _RH=\frac{12J}{3mol} =4\frac{J}{mol}$

Thus, it is important to notice that the compound "uses" the energy, it means that it absorbs the energy, for that reason the sign is positive. Moreover, computing the result in kJ/mol we finally obtain:

$\Delta _RH=4\frac{J}{mol}*\frac{1kJ}{1000J} =4x10^{-3}\frac{kJ}{mol}$

Best regards.

5 0

2 years ago

Theoretical<br> Yield of Cu<br> based on<br> Amount of CuSO4

fiasKO [112]

Answer:

I hope this helps.

Explanation:

6 0

2 years ago

A chemical engineer must calculate the maximum safe operating temperature of a high-pressure gas reaction vessel. The vessel is

TiliK225 [7]

Answer:

Maximum safe operating temperature = 450 °C

Explanation:

First, the volume of the cylindrical vessel is determined using the formula:

v = πr²h

Radius, r, of stainless steel vessel = width or diameter / 2

r = 39.0 cm / 2 = 19.5 cm

height of vessel = 46.8 cm

volume of cylinder = 22/7 × 19.5² × 46.8 = 55929.343 cm³ = 0.05593 m³

Using the ideal gas equation to calculate the maximum safe temperature

PV = nRT

pressure, P = 5.30 MPa = 5.30 × 10⁶ Pa

R = 8.314 J/mol.K

n = mass of gas/ molar mass of gas

molar mass of SF₆ = 146 g/mol

mass of Sf₆ = 7.20 kg = 7200 g

n = 7200/146 = 49.315 moles

T = PV/nR

T = (5.30 × 10⁶ × 0.05593) / (49.315 × 8.314)

T = 722.98 K

T in °C = 714.98 - 273.15 = 449.83 °C

Therefore, maximum safe operating temperature = 450 °C

5 0

2 years ago

Select the statement(s) that explain(s) the relationship between the arrangement of elements by size and first ionization energy

kow [346]

c. A full s subshell is able to shield a newly filled p subshell from the nucleus, making the first electron in a p subshell easy to remove.

Explanation:

From the given options, a full s-sublevel is able to shield a newly filled p-subshell from the nucleus thereby making the first electron in a p-subshell easy to remove is correct.

What is ionization energy?

Ionization energy is a measure of the readiness of an atom to lose an electron.

First ionization energy is the energy required to remove the most loosely held electron in the gas phase.

The size of an atom/element depends on the number of electrons it contains. The more the electrons, the larger its size.

The larger an atom becomes the lesser the ionization energy needed to remove the first electron from its outermost shell.

Electron - electron repulsion occurs when two electrons in the same sub-level repels one another.

Shielding effect is the ability of the inner electrons to protect the outer electrons from the pull of the nuclear charge.

In option C, a s-subshell has a greater shielding effect than the p,d and f sub-shell in that order.

A newly introduced electron in the p-sublevel will be loosely held and easier to remove.

Learn more:

First ionization energy brainly.com/question/2153804

#learnwithBrainly

8 0

3 years ago

Read 2 more answers

What element breaks down into yttrium-90?

atroni [7]

The correct answer is Strontium-90.

Strontium-90 breaks down into yttrium-90.

Strontium-90 is a radioactive isotope of strontium. It undergoes β− decay into yttrium-90. A decay energy of 0.546 MeV is also released.

⁹⁰₃₈Sr -> ⁰₋₁e + ⁹⁰₃₉Yr

Beta particle has the charge and mass of an electron. Upon the release of a beta particle, the mass number of Sr remains unchanged but the atomic number of Sr increases by 1. As a result both Sr and Yt have mass number 90, however, Sr and Yt have atomic numbers 38 and 39 respectively.

8 0

3 years ago