Answer:
147 g
Explanation:
<em>The number of moles of a substance is the ratio of the mass of the substance and the molar mass of that substance.</em> Mathematically,
mole = mass of substance/molar mass
In this case, Nick needs 3.5 moles of NaF, the molar mass of NaF is calculated as:
23 + 19 = 42 g/mol (Note: Na = 23, F = 19)
Hence,
mass of 3.5 mole NaF = mole x molar mass
= 3.5 x 42 = 147 g.
<em>Hence, Nick would need to measure out </em><em>147 g</em><em> NaF using a suitable weighing balance.</em>
Answer:
The energy of a hydrogen atom's electron is determined by which principal quantum number n value corresponds to the energy state the electron occupies. where n=1,2,3,... is the quantum number that quantizes the energy levels. That is, they are discrete energy values proportional to 1n2 .
Explanation:
A. High intermolecular forces of attraction. If there are high intermolecular forces, the molecules will need large energies to escape into the liquid. The substance will nave a high melting point.
The other options are <em>incorrect </em>because they are <em>weak force</em>s. They would cause <em>low melting points</em>.
