Answer:
Catalyst is a substance that increases the rate of a chemical reaction but is chemically unchanged at the end of the reaction.
properties of catalyst :
1. A catalyst increases the speed of a reaction, and it also improves the yield of the intended product.
2. A catalyst actually takes part in the reaction even though it itself is not consumed or used up in the course of the reaction.
3. A catalyst makes the reaction faster by providing an alternative pathway with a lower activation energy.
4. A catalyst is reaction-specific. It may not be effective in another reaction even if the two reactions are of similar type.
5. In a reversible reaction, a catalyst accelerates both the forward and the reverse reactions. So, the inclusion of a catalyst does not alter the equilibrium constant of a reversible reaction.
Density describes how compact or concentrated something is. For example, suppose you have two boxes, one large and one small. ... That means the small box has a higher density than the large box. Density also tells how concentrated or crowded something is.
It is important to use the same balance throughout the entire experiment since the calibration of each balance is not the same and changing balances could result in a systematic error.
There are three types of errors that could affect the results of the experiment. The effect of random or indeterminate errors is hard to predict, its effect on the results of the experiment could be different every time. The second type of error is the systematic or determinate error, which causes a shift in results in a specific direction. The last type of error in an experiment is human error.
The type of error that could be related to the use of different balances throughout the experiment is the systematic error. Instruments could be a source of error especially if they are poorly calibrated. Also, analytical balances are calibrated differently which may result in inaccuracy in the weighing of chemicals.
To learn more, please refer to brainly.com/question/11541675.
#SPJ4
Answer:
Explanation:
Use Dalton's law and the vapor pressure of water at 23.0 o C to correct the pressure to units of atmoshperes.
PT = Poxygen +Pwater
At 23.0 o C the vapor pressure of water is 21.1 mmHg. (This can be found on a vapor pressure table.)
762 mmHg = Poxygen + 21.1 mmHg
Poxygen = 762 mmHg - 21.1 mmHg
Poxygen =741 mmHg
Convert the corrected pressure to atmospheres.
(741 mmHg) (1 atm / 760 mmHg) = 0.975 atm
Use the ideal gas law to find out how many moles of gas were produced:
PV = nRT (remember to put volume in liters and temperature in Kelvin)
(0.975 atm) (.193 L) = n (.0821 L atm / mol K) (298 K)
n = (0.975 atm) (.193 L) / (.0821 L atm / mol K) (298 K)
n = 7.69 X 10-4 mol
Use the number of moles and the molecular weight of oxygen to find out how many grams of oxygen were collected.
(7.69 X 10-4 mol) (32.0 g / 1 mol) = 2.46 X 10-2 g
