Find the density of the plastic. if the density is less than that of water, it's going to float. If it's more than the density of water, then it's going to sink.
An open system is
when there is a transfer of energy and matter with its surroundings.
A closed system is
where there is a transfer of energy, may it be heat or work, but not matter
with its surroundings.
An isolated system
is where there is no transfer of energy or matter with its surroundings.
You first need to write the balanced chemical reaction for what is going on.
Ca(OH)₂+2HCl→2H₂O+CaCl₂
After you make the balanced chemical reaction, First you find the moles of HCl used. To do this multiply 0.0375L by 0.124M to get 0.00465mol HCl. Then you multiply 0.00465mol HCl by (1mol Ca(OH)₂)/(2mol HCl) to get 0.002325mol Ca(OH)₂. Finally to find concentration of Ca(OH)₂ used you divide 0.002325mol by 0.020L to get 0.116M Ca(OH)₂.
Therefore the concentration of the unknown solution of Ca(OH)₂ was 0.116M.
I hope this helps. Let me know if anything is unclear.
<h2>Answer:</h2>
This is a physical change.
<h3>
Explanation:</h3>
Hot asphalt is mixed with the sand crushed stones and spread onto the roads, when it gets dry it becomes hard giving a smooth straight surface of the road.
Asphalt is used to stick together stones and sand in the road.
It is a physical change because the phase of the asphalt changed from the liquid to solid.
At high temperature, asphalt is in liquid form and at room temperature, it is present in hard solid form.
The question is incomplete. To complete it you must include the moles of N2 and then you can use the ideal gas law to solve for the mass.
