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
So use equation: ΔH = MCΔT
M = mass of water
C = waters specific heat capacity (4.18)
ΔT = the temp. change of the reaction
ΔH = 100 x 4.18 x 10 = 4180J or 41.8KJ
so the cube absorbed 4180J of energy
hope that helps
Answer:
acceleration
Explanation:
when your at a complete stop and you take off it would be acceleration because your not arleady moving.