The answer is b. I hope this helps.
Answer:
817.66 g/mol
Explanation:
The <em>freezing point change</em> can be calculated by the formula:
Where m is the molality of the solute in NO, Kf is the cryoscopic constant (in K·kg/mol), and i is 1 in this case (because the substance in non-dissociating).
We can <u>calculate Kf of NO</u> with the information given by the problem and the formula:
Where R is the universal gas constant (8.314 J·mol⁻¹·K⁻¹), M is the molar mass of NO (30 g/mol, or 0.03 kg/mol), T f is the freezing point of NO (in K), and ΔH is the heat of fusion.
- Kf = 8.314 J·mol⁻¹·K⁻¹ * 0.03 kg/mol * (109.16 K)² ÷ 2300 J/mol = 1.292 K·kg/mol
Now we calculate the molality of the solute in NO:
<em>Molality is equal to the moles of solute per kilogram of solvent</em>:
- 0.1370 m = moles solute/ 1 kg NO
- moles solute = 0.1370 moles
With the given mass of the solute we <u>can calculate the molar mass</u>:
- 112 g / 0.1370 moles = 817.66 g/mol
Answer:
c) he describes specific locaions for the electrons
Explanation:
he determined that electron are around the nucleus in fixed orbits where as Rutherford did not give any concept of orbits. the concept of orbits also explains the change in energy levels as the electron moves from higher to lower or lower to higher energy level.
Answer:
A chemical reaction that stores energy is called an endothermic reaction. More energy might be released as products form than the energy needed to break the reactants apart. This chemical reaction will release energy. In other words, it will be an exothermic reaction.
Explanation:
An ionic compound is a compound between a metal and a non metal where the metal (normally from group 1 or 2) transferrs an electron to the non metal ( most commonly from group 6 or 7) . this is so that both atoms have a full outer shell of electrons. the metal gains a positive charge and the non metal a negative charge. they are held together by electrostatic forces of attraction. an example would be sodium chloride (salt) sodium is in group 1 and chlorine in group 7 so sodium transfers one electron :)