Explanation:
I haven't studied this in quite a long time but I will try my best to answer your question.
Gravity is a force that pulls things towards it and everything has gravity. The larger an object the stronger it's force of gravity and the more it pulls objects towards it. In our solar system the Sun is the largest object (by far) and therefore has the highest gravity. This means that the planets orbit the sun since the gravity of the sun is pulling the planets towards it. This stops planets from flying to outer space.
The thing that stops the planets from crashing into the sun is that they are travelling too fast. The planets are trying to travel in a straight direction, but the gravity and their speed in another direction kind of counteract and create a "medium" I guess you could call it, meaning the planet just orbits the sun.
First, find the volume the solution needs to be diluted to in order to have the desired molarity:
You have to use the equation M₁V₁=M₂V₂ when ever dealing with dilutions.
M₁=the starting concentration of the solution (in this case 2.6M)
V₁=the starting volume of the solution (in this case 0.035L)
M₂=the concentration we want to dilute to (in this case 1.2M)
V₂=the volume of solution needed for the dilution (not given)
Explaining the reasoning behind the above equation:
MV=moles of solute (in this case KCl) because molarity is the moles of solute per Liter of solution so by multiplying the molarity by the volume you are left with the moles of solute. The moles of solute is a constant since by adding solvent (in this case water) the amount of solute does not change. That means that M₁V₁=moles of solute=M₂V₂ and that relationship will always be true in any dilution.
Solving for the above equation:
V₂=M₁V₁/M₂
V₂=(2.6M×0.035L)/1.2M
V₂=0.0758 L
That means that the solution needs to be diluted to 75.8mL to have a final concentration of 1.2M.
Second, Finding the amount of water needed to be added:
Since we know that the volume of the solution was originally 35mL and needed to be diluted to 75.8mL to reach the desired molarity, to find the amount of solvent needed to be added all you do is V₂-V₁ since the difference in the starting volume and final volume is equal to the volume of solvent added.
75.8mL-35mL=40.8mL
40.8mL of water needs to be added
I hope this helps. Let me know if anything is unclear.
Good luck on your quiz!
If you don't wash the thermometer, residual NaOH will react with the HCl solution. This is a highly exothermic reaction and will change the temperature of the solution, and thus throw off your measurement.
Answer:
compounds
Explanation:
Substances made of two or more elements that are chemically joined together are called <u>compounds</u>.
<em>Generally, elements are substances that contain just a type of atom. Compounds, on the other hand, contain different atoms (of different elements) that are chemically linked together. The linkage is referred to as bonding. The bonding could be covalent, ionic, or hydrogen bonding.</em>
If there is a close container with some water, the following procedures take place.
Initially, the system contains only liquid, and air above it. As evaporation starts (the rate of evaporation is constant for the specific temperature of the water), the molecules from the surface of the liquid escape into vapour state, in the confined space above. Therefore, the level of liquid falls.
Then starts the process of condensation. This is the conversion of vapour into liquid. Initially, escaped molecules (from liquid state) move randomly in all directions and collide with one another. As more and more molecules enter the confined space, some slow-moving molecules are pushed back. They collide with the surface of the liquid to reconvert into liquid.
In the initial stages, the rate of evaporation (constant) is more than the rate of condensation because only small number of molecules are present in the gaseous state. The rate of condensation thereafter gradually increases as the number of molecules in the gaseous phase increases. Finally, a stage is reached when the rate of the two opposing processes is the same.
The state where the rate of evaporation becomes equal to the rate of condensation is called a state of dynamic equilibrium. In such a state, although the amount of liquid level in the container does not change, evaporation has not stopped and the system is not at rest. In fact, the number of molecules, which escape from the liquid to the gaseous phase (due to evaporation), becomes equal to the number of vapour molecules that return to the liquid
