Answer:
Explanation:
Mechanical energy = Kinetic energy + Potential energy
We shall calculate mechanical energy at different points of time .
Time Kinetic energy Potential energy mechanical energy
0 0 4 4
2 2 2 4
4 4 0 4
6 2 2 4
8 0 4 4
10 2 2 4
and so on ........
Hence we see that total mechanical energy is constant at the value of 4
at all time .
Answer:
The mass percentage of CaCO3(s) in the sample is 83.4%
Explanation:
CaCO₃ + 2HCl → CaCl₂ + H2O + CO₂
Let's find out the moles of each reactant:
[HCl] = 0.150 mol/L
Molarity . volume = moles
0.150 m/L . 0.050L = 7.5x10⁻³ moles HCl
Molar mass of CaCO₃ =100.08 g
Moles of CaCO₃ = Mass / Molar mass
0.450 g/100.08 g = 4.49x10⁻³ moles of salt
Ratio is 1:2
If 2 moles of HCl react with 1 mol of salt
7.5x10⁻³ moles of HCl react with 7.5x10⁻³ / 2 = 3.75x10⁻³ moles
We must find out the mass
Moles of CaCO₃ . Molar mass CO₃ = 0.3753 g
So now, the mass percentage of salt will be
0.450g ___ 100%
0.3753 g ____ (0.3753 .100 )/0.450 =83.4 %
Is constant (matter that has a composition that is the same everywhere)
Answer:
C. the boiling point of water
Explanation:
B is correct because boiling point only usually differs among the same substance when pressure changes. So say you take one solution onto a mountain top and another at sea level, the boiling point will not be the same, but here we assume they are in the same place so it won't.
A cannot be because the containers are all different shapes (and we aren't talking about like molecular shape of water from what I assume, we mean macroscopically, so that can't be).
B cannot be because we have 4 different temperatures.
D cannot be because we have 4 different temperatures, and therefore different amounts of steam will be released per minute as not all the waters have reached boiling.
Non-polar because hydrophilic means something can be wetted by water
