Answer:
Explanation:
The octet rule does not always refer to a stable arrangement of eight valence electrons because there are some element that do not have eight valence electrons yet they are stable. for example;
i) Helium, It has two valence electrons and it is a stable gas.
ii) Boron triflouride (BF3); it has six valence electrons (deficit valence electron) yet it is also stable.
iii) Phosphorus pentachloride (PCl5); it has more than eight valence electron and it is also stable.
For these few reasons it is not always advisable to say octet arrangement refer to stable eight valence electrons.
B is the answer. For an equation to be balanced there must be the same amount of each element on the two sides. The only one where this is the case is B.
Answer:
0.645 L
Explanation:
To find the volume, you need to (1) convert grams to moles (using the molar mass) and then (2) calculate the volume (using the molarity ratio). The final answer should have 3 sig figs to match the sig figs of the given values.
(Step 1)
Molar Mass (KOH): 39.098 g/mol + 15.998 g/mol + 1.008 g/mol
Molar Mass (KOH): 56.104 g/mol
19.9 grams KOH 1 mole
-------------------------- x ----------------------- = 0.355 moles KOH
56.014 grams
(Step 2)
Molarity = moles / volume <----- Molarity ratio
0.550 M = 0.355 moles / volume <----- Insert values
(0.550 M) x volume = 0.355 moles <----- Multiply both sides by volume
volume = 0.645 L <----- Divide both sides by 0.550
Answer:
Living organisms present in soil include archaea, bacteria, actinomycetes, fungi, algae, protozoa, and a wide variety of larger soil fauna, including springtails, mites, nematodes, earthworms, ants, insects that spend all or part of their life underground, and larger organisms such as burrowing rodents.
Explanation:
Pure substances are further broken down into elements and compounds. Mixture are physically combined structures that can be separated into their original components. A chemical substance is composed of one type of atom or molecule.
