Seeing signs of a chemical reaction does not always mean that a reaction is happening. For example, a gas (water vapor) is given off when water boils. ... You can tell that it is a physical change because water vapor can condense to form liquid water. In a chemical change, a new substance must be produced.
It is important to use chemicals of high quality and correct concentrations in experiment so that we can obtain the predictable result in an experiment
Purity of substances/chemicals is very important when performing experiments in the laboratories, because it plays an important role in the determination of the chemical properties of substances which will have a direct effect on the result obtained from the experiment. likewise using the correct concentration of reagents
During experiments to obtain the best/predictable result in an experiment it is of best practice to make use of chemicals of high quality and also at the exact(needed) concentrations, that way the predictable result of the experiment will be obtained.
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Question 1 answer: A
Question 2 answer: H
Question 3 answer: J
Question 4 answer: T
To convert from grams to moles, you divide the number of grams by the molar mass To convert from moles to grams, you multiply by the molar mass. You must first calculate the molar mass of the substance
Answer:
B. ethylamine.
Explanation:
- Since the compound contains NH₂, it is an amine compound.
- The alkyl group C₂H₅- contains 2 C atoms (ethyl group).
<em>So, the compound is ethylamine.</em>
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