Using the periodic table, find the molecular mass of H2. H2 = g/mole

Many scientists believe that the current period of global warming is related to increased levels of

OlgaM077 [116]

Option B is your answer.

5 0

3 years ago

The free energy change for the following reaction at 25 °C, when [Cr3+] = 1.32×10-3 M and [Fe3+] = 1.14 M, is 131 kJ: Cr3+(1.32×

larisa [96]

Answer:

E°cell = - 1.3575 V

This reaction is spontaneous in the reverse direction

Explanation:

The given cell reaction:

Cr³⁺(1.32 × 10⁻³ M) + Fe²⁺(aq) → Cr²⁺(aq) + Fe³⁺(1.14 M)

The given Gibbs free energy: ΔG = 131 kJ = 131 × 10³ J (∵ 1 kJ = 10³ J)

As we know,

ΔG = - n F E°cell

Here, n - the number of moles of electrons transferred = 1

F - Faraday constant = 96500

E°cell - cell potential = ?

$\therefore E^{\circ }_{cell} = -\frac{\Delta G}{n \: F} = -\frac{131\times 10^{3}\, J}{1\, mol\times96500 \, C.mol^{-1}}$

$\Rightarrow E^{\circ }_{cell} = -1.3575\, V$

For a given chemical reaction if-

1. ΔG = negative and E°cell = positive

⇒ The reaction is spontaneous and proceeds spontaneously in the forward direction.

2. ΔG = positive and E°cell = negative

⇒ The reaction is non-spontaneous and proceeds spontaneously in the reverse direction.

Since, for this chemical reaction: 

Cr³⁺(1.32 × 10⁻³ M) + Fe²⁺(aq) → Cr²⁺(aq) + Fe³⁺(1.14 M)

ΔG = + 131 × 10³ J ⇒ positive

and, E°cell = - 1.3575 V ⇒ negative

Therefore, this reaction is spontaneous in the reverse direction.

6 0

3 years ago

An indicator is_____ Select all that apply.

crimeas [40]

Answer: C

Explanation:

Indicators are organic weak acids or bases with complicated structures.

5 0

3 years ago

A chemist must calculate the amount of an element needed for a chemical reaction. The reaction requires 3.4 moles of silver. Hel

zvonat [6]

Answer:

3.4 moles of silver * 107.868 grams of silver/1 mole of silver = 370 grams of silver.

Explanation:

According to the NYS Reference Table, one mole of silver equates to 107.868 grams. Therefore, if you want to convert from moles to grams, the mole unit should be on the bottom, since it is the unit being cancelled out. Above the mole unit should be the gram unit, since it is the unit you want to convert to. Once you do the math with significant figures, the solution turns out to be 370 grams of silver.

6 0

3 years ago

Why can some electric appliances be immersed in water without damage

sukhopar [10]

Some electric appliances can be immersed in water without damage because they are well insulated. The electrical systems are well insulated and tightly sealed so that when they are immersed in water, no water can get into the electrical parts.

3 0

3 years ago