One of the differences I can think of is that hydrogen is no longer listed as a group I element.
According to the mendeleev tables that I looked up, hydrogen is catorgrized as a group I element, along with Lithium, sodium, Potassium etc. However, nowadays, hydrogen does not belong to any groups in the periodic table. This is because there are arguments about whether hydrogen belongs to group I. Group I elements are all alkali metals, while hydrogen is not. However, some people says that hydrogen only have one outer shell electron so it should be in group I. Some people even say hydrogen should belong to group VII because it only needs one more electron in order to achieve the duplet of electrons.
Therefore as you may notice, hydrogen in modern periodic tables are put in the center of the periodic table on the top.
Answer:
Wood consists mainly of organic substances (99% of the total mass). Elemental chemical composition of wood of different breeds is practically the same. Absolutely dry wood on average contains 49% of carbon, 44% of oxygen, 6% of hydrogen, 0.1-0.3% of nitrogen. When burning wood remains its inorganic part - ash.
So the answer is flammability because wood is flammable.
<span>If the decomposition of H2O2 is first order, then
rate=k*[H2O2], and k=rate/[H2O2]
In this case k=(4.83 x 10-6 M/s)/(0.15 M)
k=3.22 x 10-5 s^-1</span>
Answer:
HDL absorbs cholesterol and carries it back to the liver. The liver then flushes it from the body. High levels of HDL cholesterol can lower your risk for heart disease and stroke.
Explanation:
Answer:
(a) calculated density= 0.86 g/mL. The substance is probably toluene, density= 0.866 g/mL (b) 40.4 mL ethylene glycol (c) 1.11 x 10^3 g nickel
Explanation: