The correct answer is 2. Magnetic fields must start at the north pole of a magnet and end at the south pole of a magnet. I took the test. Hope I helped!
Missing chemical reaction:
Pb(NO₃)₂(aq) + Li₂SO₄(aq) → PbSO₄(s) + LiNO₃(aq).
Answer is:
Balanced chemical reaction:
Pb(NO₃)₂(aq) + Li₂SO₄(aq) → PbSO₄(s) + 2LiNO₃(aq).
Number of atoms on both side of chemical reaction must be the same. There is two lithium atoms, two nitrogs, ten oxygen atoms, one lead and one sulfur on both side of balanced chemical reaction.
Answer: It will take 3 days for half of a 10 g sample to decay.
Explanation:
Half-life of sample of an isotope X = 3 days
Sample decayed = 
N=
, time = t
![\ln[5 g]=-0.231 day^{-1}\times t\ln[10]](https://tex.z-dn.net/?f=%5Cln%5B5%20g%5D%3D-0.231%20day%5E%7B-1%7D%5Ctimes%20t%5Cln%5B10%5D)
![\ln[\frac{5}{10}]=-0.231\times t](https://tex.z-dn.net/?f=%5Cln%5B%5Cfrac%7B5%7D%7B10%7D%5D%3D-0.231%5Ctimes%20t)
t = 3 days
It will take 3 days for half of a 10 g sample to decay.
Answer:
Fluorine = 7 v.e.
Sulfur = 6 v.e.
Oxygen = 6 v.e.
Nitrogen = 5 v.e.
Carbon = 4 v.e.
Explanation:
Valence electrons can be easily determined by understanding groups (columns). Every element in. . .
column 3A (13) = 3 v.e.
column 4A (14) = 4 v.e.
column 5A (15) = 5 v.e.
column 6A (16) = 6 v.e.
column 7A (17) = 7 v.e.
Answer:
When it reduce then it going be real cold.
Explanation:
