Answer:
GAY-LUSSAC'S LAW.
Explanation:
P1 = 765 torr
T1 = 23°C = 296K
P2 = 560. torr
T2 = ?
(765 torr)/(296K) = (560. torr)/ T2
T2 = 226 K = -57°C
Answer:
320 g
Step-by-step explanation:
The half-life of Co-63 (5.3 yr) is the time it takes for half of it to decay.
After one half-life, half (50 %) of the original amount will remain.
After a second half-life, half of that amount (25 %) will remain, and so on.
We can construct a table as follows:
No. of Fraction Mass
half-lives t/yr Remaining Remaining/g
0 0 1
1 5.3 ½
2 10.6 ¼
3 15.9 ⅛ 40.0
4 21.2 ¹/₁₆
We see that 40.0 g remain after three half-lives.
This is one-eighth of the original mass.
The mass of the original sample was 8 × 40 g = 320 g
Answer:
It looks alittle dark can you fix it?
Answer:
3.0 × 10²⁰ molecules
Explanation:
Given data:
Mass of ethanol = 2.3 × 10⁻²°³ g
Number of molecules = ?
Solution:
Number of moles of ethanol:
Number of moles = mass/ molar mass
Number of moles = 2.3 × 10⁻²°³ g / 46.07 g/mol
Number of moles = 0.05 × 10⁻²°³ mol
Number of molecules:
One mole = 6.022 × 10²³ molecules
0.05 × 10⁻²°³ mol × 6.022 × 10²³ molecules / 1 mol
0.30 × 10²⁰°⁷ molecules
3.0 × 10¹⁹°⁷ molecules which is almost equal to 3.0 × 10²⁰ molecules.
