Answer:
2.765amu is the contribution of the X-19 isotope to the weighted average
Explanation:
The average molar mass is defined as the sum of the molar mass of each isotope times its abundance. For the unknown element X that has 2 isotopes the weighted average is defined as:
X = Mass X-19 * Abundance X-19 + MassX-21 * Abundance X-21
The contribution of the X-19 isotope is its mass (19.00 amu) times its abundance (14.55% = 0.1455). That is:
19.00amu * 0.1455 =
2.765amu is the contribution of the X-19 isotope to the weighted average
Answer:
Never pour water into acid but acid into water
Explanation:
If water is poured into extremely concentrated acid/bases, the rate of volatility and exothermic reaction is too rapid and might cause a chemical eruption, leading to acid burns.
Safety precautions hence dictate the reverse is practiced.
I believe this is a clear answer.
While the material retains its chemical makeup, the physical property may be examined. The given statement is true.
The matter can undergo variations in physical or chemical properties. The physical changes of a matter occur when the matter undergoes changes in its physical properties like changes in the state of matter, weight, color, etc.
But the chemical composition of matter will remain constant if it undergoes a physical change. Whereas in chemical change, the matter undergoes a change in the composition of the substance but there will be no change in the physical properties.
Hence, The assertion is correct in that physical properties can be seen while the substance's chemical makeup stays constant.
To learn more about physical and chemical change, visit: brainly.com/question/21509240
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Answer:
Explanation:
Hello there!
In this case, since the reaction (A->B) have an initial amount of pure 4-aminobenzoic acid, the first step to compute the theoretical yield is to solve the following stoichiometric setup:
Whereas A stands for 4-aminobenzoic acid and B for the benzocaine. Moreover, we compute the percent yield by dividing the actual yield (0.318 g) by the theoretical one (0.365 g):
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