Answer:
Hi, I think the D since the moon rotates about once a month and these months have different amounts of days. an example would be February that can have like 28 or 29 in leap year
Explanation:
The chemical reaction involving sodium and oxygen as given in the reaction: 4Na + O2 → 2Na2O is a synthesis reaction.
<h3>What are chemical reactions?</h3>
Chemical reactions are changes which occur in the chemical composition of atoms of substances which results in the formation of new substances.
There are different types of chemical reactions such as:
- synthesis reaction
- displacement reaction
- double displacement reactions
A synthesis reaction is a reaction in which two or more substances combine to form a new product.
Therefore, the chemical reaction involving sodium and oxygen as given in the reaction: 4Na + O2 → 2Na2O is a synthesis reaction.
Learn more about chemical reactions at: brainly.com/question/11231920
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Answer:
25 mM Tris HCl and 0.1% w/v SDS
Explanation:
A <em>10X solution</em> is ten times more concentrated than a <em>1X solution</em>. The stock solution is generally more concentrated (10X) and for its use, a dilution is required. Thus, to prepare a buffer 1X from a 10X buffer, you have to perform a dilution in a factor of 10 (1 volume of 10X solution is taken and mixed with 9 volumes of water). In consequence, all the concentrations of the components are diluted 10 times. To calculate the final concentration of each component in the 1X solution, we simply divide the concentration into 10:
(250 mM Tris HCl)/10 = 25 mM Tris HCl
(1.92 M glycine)/10 = 0.192 M glycine
(1% w/v SDS)/10 = 0.1% w/v SDS
Therefore the final concentrations of Tris and SDS are 25 mM and 0.1% w/v, respectively.
