Answer: caffeine is a compound.
Explanation:
1) As stated c<span>affeine contains hydrogen, carbon, nitrogen, and oxygen atoms in a fixed ratio.
2) The definition of compound is a pure substance formed by chemical bonding of two or more fifferent elements. That means a defined ratio of the elements in the compound, which conferes uniform and equal properties to every part of the compound.
Some examples of compounds are salt (NaCl), water (H2O), vinegard (CH3 COOH).
A mixture combines several elements or compounds, not bonded by chemical bonds but mixed in ratios which may vary.
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3 mass number- proton number
Answer:
15m
Explanation:
vi = 0
vf = 10
a = -9.8
10^2 = 0 + 2(-9.8)(x2-x1) = -5.1
20-5.1 = 14.9m = 15m
Answer : The pressure in the flask after reaction complete is, 2.4 atm
Explanation :
To calculate the pressure in the flask after reaction is complete we are using ideal gas equation.
where,
P = final pressure in the flask = ?
R = gas constant = 0.0821 L.atm/mol.K
T = temperature = 
V = volume = 4.0 L
= moles of 
= 0.20 mol
= moles of 
= 0.20 mol
Now put all the given values in the above expression, we get:
Thus, the pressure in the flask after reaction complete is, 2.4 atm
Yo sup??
we can solve this problem by applying Newton's 2nd law
F*t=Δp
p=momentum
pi=mu=1500*30
pf=mv=m*0=0
Therefore
F*3=1500*30
F=15000 N
Hope this helps.
