To be able to determine the number of moles that a certain number of molecules comprises, we simply divide the number of molecules by the Avogadro's number which is equal to 6.022 x 10^23.
n = M/A
where n is the number of moles, M is the number of molecules, and A is Avogadro's number. Substituting the known values,
n = (4.15 x 10^23 molecules)/(6.022 x 10^23 molecules/mol)
Simplifying,
n = 0.689 moles
<em>Answer: 0.689 moles</em>
Endothermic energy is taking place. The sausage is being heated by the fire and absorbing the thermal energy.
Answer:
3290 gm
Explanation:
6.56 pints * 473.1765 ml/pint * 1.060 g/ml = 3290 gm
Answer:
the mas is .291 g
Explanation:
the mass of a object does not change. so when added the substance the beaker. you had the mass of both objects together. you know the mass of the beaker and you know the mass of both. since mass does not change. the beakers mass is still 74.605g. the mass of both objects is 74.896. all you have to do is subtract the mass of the beaker from the total mass. 74.896 - 74.605 equals .291g. so the mass of the unknown substance Is .291g
Answer:
1.115 g
Explanation:
Applying,
R = R'
................... Equation 1
Where R = original sample of radon-222, R' = sample of radon-222 left after decay, n = Total time, t = half-life.
make R' the subject of the equation
R' = R/()............... Equation 2
From the question,
Given: R = 73.9 g, n = 23 days, t = 3.8 days.
Substitute these values into equation 2
R' = 73.9/(
)
R' = 73.9/
R' = 1.115 g
