Answer:
a chemical change is a change that changes the substance into a whole new substance.
Examples include: burning wood, a banana peel rotting, milk souring, and even your food/drinks digesting.
Answer:
Chromatography is a method of separation of materials from a mixture. Paper chromatography is a technique of separation where, paper used as a stationary phase and solvent used to separate the sample used as a mobile phase. The sample is applied over the paper in small quantity. The components of the sample separates in a chromatographic paper due to the movement of solvent. The components of the sample moves with the solvent.
Paper chromatography is a useful technique for ink analysis. Ink consists of several dyes, which can be separated individually. When the ink is exposed to certain solvent mixtures the dyes of the ink dissolves in the mixture. Each ink components acquire distinct distance according to the retention factor. Some inks are water soluble, so the solvent used for separation should be water. Inks which are not water soluble are soluble in other solvents like alcohol.
Answer:
P2 = 2.25 atm
Explanation:
Given:
V1 = 1.5 L. V2 = 2.0 L
P1 = 3.0 atm. P2 = ?
Use Boyle's law and solve for P2:
P1V1 = P2V2
or
P2 = (V1/V2)P1
= (1.5 L/2.0L)(3.0 atm)
= 2.25 atm
Answer:
True.
Explanation:
To know which option is correct, let us calculate the number of mole present in 60g of calcium. This is illustrated below:
Mass of Ca = 60g
Molar Mass of Ca = 40g/mol
Number of mole Ca =....?
Number of mole = Mass/Molar Mass
Number of mole of Ca = 60/40
Number of mole Ca = 1.5 moles.
From the calculations made above, we can see that 1.5 moles are present in 60.0 grams of calcium
