Answer:
Explanation:
Examples of pure substances include tin, sulfur, diamond, water, pure sugar (sucrose), table salt (sodium chloride) and baking soda (sodium bicarbonate). Crystals, in general, are pure substances. Tin, sulfur, and diamond are examples of pure substances that are chemical elements.
We do a heat balance to solve this:
(m cp ΔT)water = -(m cp ΔT)metal
100.8 (4.18) (27 - 22) = -65 (cp)(27-100)
cp = 100.8 (4.18) (27 - 22) / (-65 (27-100))
cp = 0.44 J/ (°C × g)
The specific heat of the metal is 0.44 J/ (°C × g)
Explanation:
Hi for this one u just need to remember and use the equation.
then u find mr of potassium which is 39.1.
then u do
you get the answer as 0.5115 write ur answer to 3 significant figures which will be 0.512 moles .
hope this helps :)
Answer:
The main difference between the two models is <em>the position of the electron in the atom</em>.
Explanation:
- <em>Bohr model:</em> The electrons are moved around the nucleus in circular definite paths (orbitals or shells). Also, he could not find or detect the exact position of electron.
- <em>Electron cloud model:</em> It is supposed by Erwin Schrodinger. He showed that the emission spectra of the atom is the way to detect the probability of electron position.
Answer:
162 g Fe₂O₃
Explanation:
To find the mass of Fe₂O₃, you need to (1) convert grams C to moles C (via molar mass from periodic table), then (2) convert moles C to moles Fe₂O₃ (via mole-to-mole ratio from reaction coefficients), and then (3) convert moles Fe₂O₃ to grams (via molar mass). It is important to arrange the ratios/conversions in a way that allows for the cancellation of units. The final answer should have 3 sig figs to reflect the given value.
Molar Mass (C): 12.011 g/mol
2 Fe₂O₃(s) + 3 C(s) ---> 4 Fe(s) + 3 CO₂(g)
Molar Mass (Fe₂O₃): 2(55.845 g/mol) + 3(15.998 g/mol)
Molar Mass (Fe₂O₃): 159.684 g/mol
18.3 g C 1 mole 2 moles Fe₂O₃ 159.684 g
-------------- x ---------------- x ------------------------- x ----------------- = 162 g Fe₂O₃
12.011 g 3 moles C 1 mole
