I had this quiz too. The answer is carbon, hydrogen, oxygen. Hope this helps!
Answer:
Gasoline isn't a pure substance.
Explanation:
A typical boiling range for gasoline is 100–400F. Gasoline has a vapor pressure of 7 psi in the summer, comparing it to water pressure it's less then 0.3 psi. For example if you spill water on a flat surface it might take a few minutes or hours to completly evapourate. Gasoline on the other hand it will evapurate within a few minutes, that's an example of volatility. Hope this helps
Answer:
There are 26 valence electrons in SOF₂.
Explanation:
Valence electrons are calculated by adding the valence electrons present in valence shell of each element present in SOF₂. So,
# of Valence e⁻s in S = 6
# of Valence e⁻s in O = 6
# of Valence e⁻s in F = 7
# of Valence e⁻s in F = 7
Now, add all valence electrons,
= 6 + 6 + 7 + 7
= 26 Valence Electrons
Answer:
66.4g
Explanation:
Given parameters:
Mass of AgNO₃ = 69.1g
Unknown:
Mass of Ag₂CrO₄
Solution:
2AgNO₃+ Na₂CrO₄ ⟶ Ag₂CrO₄ + 2NaNO₃
The given equation is balanced.
To solve this problem, solve from the known to the unknown;
1. Find the number of moles of AgNO₃;
Number of moles =
atomic mass of Ag = 107.9g/mol
N = 14g/mol
O = 16g/mol
Molar mass of AgNO₃ = 107.9 + 14 + 3(16) = 169.9g/mol
Number of moles = = 0.41moles
2. From the balanced equation;
2 moles of AgNO₃ produced 1 moles of Ag₂CrO₄ ;
0.41 moles of AgNO₃ will produce = 0.2moles of Ag₂CrO₄
3:
Mass of Ag₂CrO₄ = number of moles x molar mass
Atomic mass of Ag = 107.9g/mol
Cr = 52g/mol
0 = 16g/mol
Molar mass = 2(107.9) + 52 + 4(16) = 331.8g/mol
so, mass of Ag₂CrO₄ = 0.2 x 331.8 = 66.4g
You would add water to the mixture to dissolve the salt. When the salt is dissolved, you have your sand alone.