Answer: Each trial was repeated several times during the experiment.
A scientific design refers to a scientific plan or methodology, which needs to be followed to perform a experiment so as to obtain accurate and appropriate result matching with the situation of the hypothesis. Each trial was repeated several times during the experiment best describes an experiment that had a good scientific design because trials in an experiment brings either concordant or consistent results or inconsistent results. The concordant results suggests that the methodology applied is correct, and inconsistent results show that methodology applied is incorrect.
Answer:
8.11g
Explanation:
Given parameters:
Molarity of aqueous solution = 0.3M
total volume = 0.15L
Molecular weight of glucose = 180.6g/mol
Unknown:
Mass of glucose needed in the solution = ?
Solution:
To solve this problem, we need to understand molarity.
Molarity is the number of moles of solute in a given volume of solution. In this problem, the solute here is the glucose and the solvent is water.
Molarity = 
A solution is made up of solute and solvent.
now, let us solve for the number of moles of the solute which is glucose;
Number of moles of glucose = molarity x volume of solution;
= 0.3 x 0.15
= 0.045mole
Now to find the mass of glucose;
mass of glucose = number of moles x molar mass
input the parameters;
Mass of glucose = 0.045 x 180.16 = 8.11g
Answer:
The liquid boils.
Explanation:
Vapor pressure is simply defined as the pressure exerted on a substance (solid/liquid) by the vapor of the substance collected just at the top of the surface of the substance. In concise words, it is the pressure of Vapor that is in contact with its solid or liquid state.
For a liquid, it is the pressure of the Vapor gathering at the top of the surface of the liquid.
When this Vapor pressure matches the external pressure, the temperature stays constant and the molecules of the liquid all through the liquid can gain enough energy, rise to the surface of the liquid and break free in gaseous form; thereby, boiling.
The definition of boiling point basically explains that it is the point at which temperature stays constant, and the vapour pressure of the liquid matches the atmospheric/external pressure around the liquid and its liquid molecules change into vapor.
This is why liquids boil faster at higher altitudes; the atmospheric pressure at higher altitudes is reduced, hence, the temperature at which liquid boils at this high altitude is normally lower than its known boiling point temperature.
It is also why food cooks to a temperature higher than the boiling point of water in a pressure cooker/pot. The added pressure ensures that the cooking water boils at temperatures higher than its boiling point; thereby exposing the cooking ingredients to a higher temperature, leading to faster cooking.
Hence, it is obvious why boiling is the answer to this question.
Answer:
Molecular compound and ionic compound
Explanation:
Molecular compounds include a prefix on the first and second elements and a suffix on the second element, whereas Ionic compounds do not have prefixes and only include a suffix on the second element.
Friction is helpful:
- We use it to brake for cars
- We use it to fly planes
-We wouldn't be able to turn a door knob without friction ( Our hand would just slide off it)
Friction harmful:
-Our cars would get much better gas mileage without tire and air friction
- There would be no skinned knees if friction didn't exist (Like when your skating or football)
- We could do some pretty cool dance moves without friction
- Our shoes would last longer without friction
