Answer:
1. 1568 J
2. 0 J
3. 1176 J
Explanation:
PE = mgh
(PE = Potential Energy) = (m = mass)(g = gravitational force which is 9.8)(h = height)
1. (3)(9.8)(20) = 1568 J
2. PE = (3)(9.8)(0) = 0 J
3. (5)(9.8)(24) = 1176 J
Answer: 0.529 atm
Explanation:
Combined gas law is the combination of Boyle's law, Charles's law and Gay-Lussac's law.
The combined gas equation is,
where,
= initial pressure of gas = 0.998 atm
= final pressure of gas = ?
= initial volume of gas = 2 L
= final volume of gas = 3.5 L
= initial temperature of gas = 
= final temperature of gas = 
Now put all the given values in the above equation, we get:
Thus the pressure if it is brought to a higher altitude where it now occupies 3.5 L and is at 12.0 °C is 0.529 atm
Answer:
E = 4.78×10^−19 J
Explanation:
The chemical equation for the energy of a photon is given by:
E =hν , where h is the Planck constant and ν is the frequency.
E =hν = 6.626×10^−34 Js × 7.21×10^ 14
s−1 = 4.78 × 10^−19 J
given days = 42 days
So, number of half life, n = 42/14.3 = 2.93
So, after 42 days, the mass of sodium phosphate sample left = original mass
x (1/2)^n,
= 157 mg x (1/2)^2.93 = 20.60 g of Na3PO4 after 42 days
Formula mass of Sodium phosphate = 3(23) + 32 + 4(16) amu = 165 amu
165 g of sodium phosphate contains 32 g of Phosphorus
20.60 g ------------------------------? = 20.60 x 32/ 165 =3.99g of P32
