Answer:
The reaction rate is inversely proportional to the reaction time.
Explanation:
- The reaction rate is the change of the concentration of reactants and products with the time.
<em>∵ Reaction rate = - Δ[reactants]/Δt = Δ[products]/Δt.</em>
<em>∴ The reaction rate is inversely proportional to the time, as the reaction rate increases it will take a lower time.</em>
1) B, Not 100% sure though
2)Building a rocket is a physical change technically its not changing its composition its just changing its appearance, the fuel for it causes a chemical change, there is an answer that is more clear, Grinding chalk into a fine powder only changes its shape which is a physical change.
Answer:
Idk if this is right but i hope it helps... sorry if it's wrong
Explanation:
The simple machine used is called atwood machine.
Your first step should be to analyse the compound. For example, if the compound is carbon, you know it always has a valence of four, so, if it has a formula C2H4 (ethylene) it obviously has a double bond. There are difficulties here because benzene C6H6 can be considered to have 6 1.5 C-C bonds, being aromatic.
A second step is to look at its structure. Double bonds are traditionally shorter than single bonds; triple bonds shorter still. Covalent bonds do have typical lengths, nevertheless you can still have problems.
<span>A third step is to consider reactivity. For example, if you have a C=C double bond, you can add, say, bromine to it Thus C2H4 gives C2H4Br2, and by adding two bromine atoms you know you have one double bond. Again, benzene becomes an awkward molecule, but because of this, you know benzene does not have double bonds in the traditional sense</span>