1-There are 18 volcanoes in the US with the potential to erupt again, all of them in Alaska, Hawaii and the West Coast states.
2-Rubies and sapphires are actually the same mineral - corundum. The basic chemical formula of corundum is Al2O3, but traces of iron stain the mineral red (ruby) while traces of chromium or titanium stain the mineral blue (sapphire).
3-Rubies, sapphires and emeralds are all more rare than diamonds.
4-Not all diamonds are transparent. They come in a variety of colors (called "fancies"), including yellow, green, blue, orange, brown ("champagne"), purple, grey, black (called carbanado, recently shown to be meteroic), milky white, pink, and red. Red is by far the rarest.
5-Antacids taste like chalk because they ARE chalk, a.k.a. calcium carbonate.
Hope this helps, Give a thanks ! Haha
Answer:
c. 5days
Explanation:
there is no question but if it's a graph
the answer is 5days
What types of atoms typically form covalent bonds?
The correct answer:
d) Nonmetals with nonmetals, because their difference in electronegativity is below 1.7.
En example to explain:
An example of a covalent bonding: HCl -> 2 nonmentals
-> a difference in electronegativity less than 1.7:
EN(Cl) = 3.0 and EN (H) = 2.1 (you can search these values in a periodic table)
/\EN = 3.0 - 2.1 = 0.9
0.9 < 1.7
I hope this helped you out!
Answer:
-145.2kJ
Explanation:
Enthalpy is an extensive property as its value depends on the amount of substance present in the system.
If the enthalpy for one mole of methanol = -726 kJ/mol;
The Enthalpy for 0.2 mol is given as;
Enthalpy = 0.200 * 726
Enthalpy = -145.2kJ
It would take -145.2kJ for 0.200 mol of methanol to undego the combustion reaction.
9 Ways to Prevent Rust
Use an Alloy. Many outdoor structures, like this bridge, are made from COR-TEN steel to reduce the effects of rust. ...
Apply Oil. ...
Apply a Dry Coating. ...
Paint the Metal. ...
Store Properly. ...
Galvanize. ...
Blueing. ...
Powder Coating.
