Answer:
Option D. Iron and sulfur react to form iron sulfide
Explanation:
Reaction of iron with sulphur is a chemical property and not a physical property.
Answer:
0.50 mol
Explanation:
The half-life is <em>the time required for the amount of a radioactive isotope to decay to half that amount</em>.
Initially, there are 8.0 moles.
- After 1 half-life, there remain 1/2 × 8.0 mol = 4.0 mol.
- After 2 half-lives, there remain 1/2 × 4.0 mol = 2.0 mol.
- After 3 half-lives, there remain 1/2 × 2.0 mol = 1.0 mol.
- After 4 half-lives, there remain 1/2 × 1.0 mol = 0.50 mol.
The reaction that releases energy as heat is called an Exothermic reaction. This reaction does obey the law of conservation by preserving the energy present in the molecule and converting it to thermal heat to maintain it's from. Most reactions obey the law of conservation of energy.
You should never taste anything in a lab.
Litmus paper will only tell you whether it is an acid or a base, not how strong it is a hydrogen test only works with acids.
You can get a serious burn from touching strong acids and bases and it doesn't give an objective measure of the strength.
The only one that is left is conductivity. This is safe and rather reliable, because the "strength" of an acid or a base depends on how much it dissociates. Hence more dissociation means greater conductivity.
