Diagram of the nuclear composition, electron configuration, chemical data, and valence orbitals of an atom of neodymium-144 (atomic number: 60), an isotope of this element. The nucleus consists of 60 protons (red) and 84 neutrons (orange). 60 electrons (white) successively occupy available electron shells (rings).
Answer:
C. 0.4.
Explanation:
<em>∵ mole fraction of acetic acid (X acetic acid) = (no. of moles acetic acid)/(total no. of moles) = (no. of moles acetic acid)/(no. of moles of acetic acid + no. of moles of water).</em>
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- no. of moles of acetic acid = 2, no. of moles of water = 3.
- Total no. of moles = no. of moles of acetic acid + no. of moles of water = 2 + 3 = 5.
<em>∴ mole fraction of acetic acid (X acetic acid) = (no. of moles acetic acid)/(total no. of moles) =</em> (2)/(5)<em> = 0.4.</em>
(3.5mol)(24.106 g/1mol c6h6) =84.371 g C6H6
Answer:
1.53 × 10²² atoms Ag
Explanation:
Step 1: Define conversions
3.271 × 10⁻²² g = 1 atom
Step 2: Use Dimensional Analysis
= 1.52858 × 10²² atoms Ag
Step 3: Simplify
We have 3 sig figs.
1.52858 × 10²² atoms Ag ≈ 1.53 × 10²² atoms Ag
It showed that the nucleus is positively charged, and that the atom isn't just made of electrons.