Answer: #1 The poppy seeds represent the protons, electrons and neutrons
#2 The fiberfill represents the nucleus #3 Protons and neutrons are in the nucleus #4 Electrons are the particles that are surrounding the nucleus #5 Because they are representing different things and they are their own entity
Hope this really does help! : ⊃
The boiling points need to differ by 50 degrees to enable their complete separation ie of two different liquids. The separation occurs by first evaporation of one of the liquids and then its condensation and collection. It is a physical process not a chemical one.
72.0726 is the percent for carbon
Answer:
32.8%
Explanation:
All of the Pb⁺² species precipitated as lead(II) cromate, PbCrO₄ (we know this as excess K₂CrO₄ was used).
First we convert 0.130 g of PbCrO₄ into moles, using its molar mass:
- 0.130 g ÷ 323 g/mol = 4.02x10⁻⁴ mol PbCrO₄
There's 1 Pb⁺² mol per PbCrO₄ mol, so in total 4.02x10⁻⁴ moles of Pb⁺² were in the ethanoate sample.
We <u>convert those 4.02x10⁻⁴ moles of Pb into grams</u>:
- 4.02x10⁻⁴ mol * 207 g/mol = 0.083 g Pb
Finally we calculate the percentage composition of Pb:
- 0.083 g Pb / 0.254 g salt * 100% = 32.8%
