Answer:
controlled by the Arabs, who brought frankincense and myrrh by camel caravan from South Arabia.
Answer:
Henry Moseley
Explanation:
Dmitry Mendeleef and Lothar Meyer proposed a periodic table based on the atomic mass.
They stated a periodic law expressed as "chemical properties of elements are a periodic function of their atomic weights".
But, Henry Moseley in 1900s re-stated periodic law by changing the basis of the law from atomic weight to atomic number.
The present periodic law is stated as "the properties of elements are a periodic function of their atomic number".
Answer:
They get more energy, so they vibrate!
Explanation:
Decay is a type of degradation reaction and thus is considered a first order reaction. thus the formula goes like this.
rate constant= 0.693/half life
so here...
rate constant= 0.693/1620 year^-1
Answer:
Explanation:
Primary and secondary succession occur after both human and natural events that cause drastic change in the makeup of an area. Primary succession occurs in areas where there is no soil and secondary succession occurs in areas where there is soil.
In primary succession, newly exposed or newly formed rock is colonized by living things for the first time. In secondary succession, an area previously occupied by living things is disturbed—disrupted—then recolonized following the disturbance.
Hope this helped :)
-<em>Akito</em>