Answer:

Explanation:
Hello,
In this case, the unit of concentration is molality which is defined by:

Whereas the mass of the solvent is measured in kilograms. In such a way, with the given data, we first compute the kilograms of water:

Then, we solve for the moles of the solute:

Finally since the molar mass of ethanol is 46 g/mol, we compute the grams for the given solution:

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Answer:
1s2 2s2 2p2
Explanation:
it has 6 electrons in two energy levels so the sub levels are 1s, 2s and 2p
Its A. because it measures the rate of the decay of the isotope
Answer:
read down below
Explanation:
Building on the Curies' work, the British physicist Ernest Rutherford (1871–1937) performed decisive experiments that led to the modern view of the structure of the atom. ... Because it was the first kind of radiation to be discovered, Rutherford called these substances α particles.