Explanation:
A system can be either closed or open; A closed system is a system that is completely isolated from its environment. An open system is a system that has flows of information, energy, and/or matter between the system and its environment, and which adapts to the exchange.
<h3>Answer:</h3>
18.75 grams
<h3>Explanation:</h3>
- Half-life refers to the time taken by a radioactive material to decay by half of the original mass.
- In this case, the half-life of element X is 10 years, which means it takes 10 years for a given mass of the element to decay by half of its original mass.
- To calculate the amount that remained after decay we use;
Remaining mass = Original mass × (1/2)^n, where n is the number of half-lives
Number of half-lives = Time for the decay ÷ Half-life
= 40 years ÷ 10 years
= 4
Therefore;
Remaining mass = 300 g × (1/2)⁴
= 300 g × 1/16
= 18.75 g
Hence, a mass of 300 g of an element X decays to 18.75 g after 40 years.
The law of conservation of mass states that in a chemical reaction, the total mass of reactants is equal to the total mass of products. ... Because atoms are only rearranged in a chemical reaction, there must be the same number of sodium atoms and chlorine atoms in both the reactants and products.
Answer:
The best reagents that are used for the conversion of ethylbenzene to (2-bromoethyl)benzene is shown in the first diagram attached.
Explanation:
Concepts and reason
The concept used to solve this problem is by using the given reagents, possible products will be formed in each step and then label it exactly in the given boxes in order to form the exact product.
Here, the starting reactant is ethyl benzene and the final product is (2-bromoethyl)benzene.
Fundamentals
Bromine molecule is used for bromination of alkene. Trans addition takes place.
Addition of HBr to the double bond forms an alkyl bromide.
Potassium tertiary butoxide is a sterically hindered base.
Bromination of alkane in the presence of sunlight gives radical substitution.
NBS (N-bromosuccinimide) is used for the allylic bromination.
The reaction is as shown in the second attachment(pictures 2,3 and 4).
<h3>Oxidising Agent</h3>
<h3>Hope it helps you Please mark me as brainliest otherwise I will leave Brainly please.</h3>
