A physical change.
Physical change = can be reverted + doesn't change substance
Chemical = changes substance
Answer - Its atomic number is 2, so it has two protons in its nucleus. Its nucleus also contains two neutrons. Since 2 + 2 = 4, we know that the mass number of the helium atom is 4.
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Answer:
150.000 g
Explanation:
The law of conservation of mass states that the mass of reactants and products of a reaction must be equal to one another.
In other words, for this case:
- Mass of KOH + Mass of HCl = Mass of Products
We are given all required data to<u> calculate the mass of the KOH solution</u>:
- Mass of KOH + 250.000 g = 400.000 g
Answer:
Paper chromatography would separate the pigments into several bands that appear green or yellow/orange.
Explanation:
Chloroplasts have a mixture of pigments with different colors: intense green chlorophyll-a, green chlorophyll-b, yellow carotenes and orange-yellow xanthophylls, in different proportions. All these substances have a different degree of solubility in non-polar solvents, which allows their separation when a solution of them ascends by capillarity through a porous paper strip, vertically arranged on a film of an organic solvent, where the most soluble move faster, and the less soluble move less on the filter paper strip. Therefore, several bands of different colors will appear that will be more or less distant from the solution according to the greater or lesser solubility of the pigments.