Answer : To find the molar mass of unknown gas we need to solve the equation of rate of diffusion and molecular weight of the gases, which is as follows;
here the mol wt of gas B is not known so we take it as '<em>x'
</em>on solving we get 7 X
/ 4.9 X
<em>
</em>mol. wt of unknown gas =
20.0 g
The characteristic of the compound you are referring is essential to where on the functional groups it belong. Furthermore, the basic functional groups among the hydrocarbons are: alkane, alkene, alkyne, benzene, and others that basically has a hydrogen atom and a carbon atom.
Answer:
false
Explanation:
in 1869 Dimitri Mendeleev a Russian chemist development the periodic table arranging elements by atomic mass
Answer:
There are 26 valence electrons in SOF₂.
Explanation:
Valence electrons are calculated by adding the valence electrons present in valence shell of each element present in SOF₂. So,
# of Valence e⁻s in S = 6
# of Valence e⁻s in O = 6
# of Valence e⁻s in F = 7
# of Valence e⁻s in F = 7
Now, add all valence electrons,
= 6 + 6 + 7 + 7
= 26 Valence Electrons
Answer: False
Explanation:
The repression of lac operon is mediated by the catabolite activator protein (CAP). The RNA polymerase can attach to promoter site, only when CAP combined with cAMP is available. Bacteria only accumulate cAMP only when starved. But when glucose is present, cAMP is not available and so CAP-cAMP is not formed. Hence the lac structural genes is turned off in the present of glucose.
Therefore the mechanism by which glucose inhibits the expression of the lac structural genes is by catabolite repression.
Whereas the process by which lactose stimulates the expression of lac operon is by derepression/allosteric regulation. Lactose binds to the lac repressor and deactivate it by causing it to change shape so it doesn't bind to the DNA