NO alkenes can not react with potassium dichromate
Answer : The mass of oxygen formed must be 3.8 grams.
Explanation :
Law of conservation of mass : It states that mass can neither be created nor be destroyed but it can only be transformed from one form to another form.
This also means that total mass on the reactant side must be equal to the total mass on the product side.
The balanced chemical reaction will be,

According to the law of conservation of mass,
Total mass of reactant side = Total mass of product side
Total mass of
= Total mass of 
As we are given :
The mass of
= 25.3 grams
The mass of
= 23.4 grams
So,



Therefore, the mass of oxygen formed must be 3.8 grams.
Answer: C
Explanation: A lunar month is 29.53 earth days. Since an earth calendar as only integer days, it could be either 29 or 30 days later.
The amount of substance present in a certain object with a given half-life in terms of h can be expressed through the equation,
A(t) = (A(o))(0.5)^(t/h)
where A(t) is the amount of substance after t years and A(o) is the original amount. In this item we are given that A(t)/A(o) is equal to 0.89. Substituting the known values,
0.89 = (0.5)(t / 5730 years)
The value of t from the equation is 963.34 years.
<em>Answer: 963 years</em>
Answer:
1s2 2s2 2p3
Explanation:
we know that the number of electrons in an atom is equal to number of protons. So the number of electrons here is 7.
Using Moller chart, the electronic configuration is writen by the electrons first enterring into 1s then into 2s after 2p. The s orbital accomodates maximum of 2 electrons.
∴ for atomic no. 7 nitrogen atom, electronic configuration is 1s2 2s2 2p3.