Answer:
to be precise in the calculations
Explanation: for example your cell phone has a gps inside it, the gps is responsible for providing direction data like a compass, if the equipment is not calibrated, the gps will not find the correct direction.
You would have to use the ideal gas law: PV = nRT where,
P = pressure
V = volume
n = moles
R = universal gas constant for a specific pressure (in this case it's 62.364 torr)
T = temperature in Kelvin
First, convert Celsius to kelvin by adding 273 to 25, which gives you 298K
Now plug in your variables to find n:
(800 torr)(1.25 L) = n(62.364)(298K)
1000 = 18584.472n
Now divide 1000 by 18584.472 to get n:
1000/18584.472 = 0.054 moles
A. The number of valence electrons increases as atomic mass increases. == Generally true for the representative elements since atomic mass generally increases with increasing Z.
B. The reactivity of alkali metals increases as atomic mass increases. == True. Atomic mass increases down the column and so does reactivity
C. The reactivity of the halogens increases as atomic mass increases. == False. Reactivity decreases down the column.
D. The number of valence electrons decreases across a period. == False. In general, the number of valence electrons increases across a period, particularly for the representative elements.
Not quite sure what you're asking, but I think what you're looking for is 'Native Species'.
Answer:

Explanation:
Hello!
In this case, given the mass, temperature change and specific heat, it is possible to compute the required heat in joules as shown below:

Now, since 1 cal =4.184 J, this result in calories is:

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