Physical change is the change we can see with our eyes. Chemical change is the change that we cannot see. Examples: physical change: The Polar ice caps are melting, and we can see that as it happens. Chemical change: The cooking of an egg or some combustion, like a fire. We can't see the chemicals coming from the fire, but there are chemicals coming from what is being burned and is being released into the air that we cannot see.
The number 345,000 has 3 significant figures because the trailing zeros are not significant since there's no decimal point.
<h3>What is significant figures?</h3>
Significant figures of a number in positional notation are digits in the number that are reliable and necessary to indicate the quantity of something.
Also significant figures can be defined as, the number of digits in a value, often a measurement, that contribute to the degree of accuracy of the value.
Examples of significant figures;
- 405 = 3 significant figures
- 405000 = 3 significant
- 0.040500 = 5 significant figures
<u>Note:</u> leading zeros are not significant but trailing zeros, which are zeros at the end of a number, are significant only if the number has a decimal point.
345,000 = 3.45 x 10⁵ (3 significant figures)
Thus, the number 345,000 has 3 significant figures because the trailing zeros are not significant since there's no decimal point.
Learn more about significant figures here: brainly.com/question/24491627
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Hydrolysis of Methyl Benzoate yields Benzoic Acid and Methanol. This reaction is also called as
Tranesterification (reverse of esterification). Acid in this reaction protonates the carbonyl oxygen, resulting in increasing electrophillic character of carbonyl carbon. Water acts as a nucleophile and methoxide leaves as a good leaving group.
Mechanism is shown below,
Use this formula PV=nRT
Rearrange formula , question want V ,so
V=nRT/P
given
P= 3.00 atm
n=0.450 moles
R is ideal gas constant = 0.08206 L atm mol-¹K-¹
T in Kelvin so , (75 + 273)= 348 Kelvin (K)
Then insert all this information given with that rearranged formula V=nRT/P
- so, V= (0.45)(0.08206)(348) / 3.00
- = 4.284 L