The number of moles in each sample will be 0.391 moles, 30.7 moles, 0.456 moles, and 1350 moles
<h3>What is the number of moles?</h3>
The number of moles of a substance is the ratio of the mass of the substance to the molar mass.
In other words; mole = mass/molar mass.
Thus:
- moles of 18.0 g
= 18.0/46
= 0.391 moles
- moles of 1.35 kg
= 1350/44
= 30.7 moles
- moles of 46.1 g
= 46.1/101.1
= 0.456 moles
- moles of 191.8 kg
= 191800/142
= 1350 moles
More on the number of moles of substances can be found here: brainly.com/question/1445383
#SPJ1
Answer:

Explanation:
Hello.
In this case, since this is a system in which the water is heated up and the metal is cooled down in a calorimeter which is not affected by the heat lose-gain process, we can infer that the heat lost by the metal is gained be water, it means that we can write:

Thus, in terms of masses, specific heats and temperatures we can write:

Whereas the equilibrium temperature is the given final temperature of 28.4 °C and we can compute the specific heat of the metal as shown below:

Plugging the values in and since the density of water is 1.00 g/mL so the mass is 80.0g, we obtain:

Best regards!
6.8x10^5? Scientific notation
Answer:
+1.03 V
Explanation:
The standard emf of the voltaic cell is the value of the standard potential of it, which is calculated by the standard reduction potential (E°).
The standard reduction potential is the potential needed for the reduction reaction happen, and it's determined by the reaction with the hydrogen cell (which has E° = 0.0V). The half-reactions of reduction of Ni⁺² and Ag⁺, are:
Ni⁺²(aq) + 2e⁻ → Ni(s) E° = -0.23 V
Ag⁺(aq) + e⁻ → Ag(s) E° = +0.80 V
The value is calculated by a spontaneous reaction, in which the cell with the greater E° is reduced (gain electrons), and the other is oxidized (loses electrons). So, Ag⁺ reduces.
emf = E°reduces - E°oxides
emf = 0.80 - (-0.23)
emf = +1.03 V
<span>oxidizing substance removes electrons from another substance, which are then added to itself, the oxidizing substance becomes “reduced” (more negative). And because it “accepts” electrons .</span>