When making 10X TBS (200mM Tris pH 8, 1.4M NaCl) the instructors realized that they did not have NaCl in a solid form. But they did have 3.5L of a 16.2% NaCl solution. How much of this solution did they use to make 1L of 10X TBS?

0.2 l.

Explanation:

Concentration of NaCl on TBS = 1.4M

Molar mass = 23 + 35.5

= 58.5 g/mol

Density of NaCl in TBS = concentration * molar mass

= 58.5 * 1.4

= 81.9 g/l

Assuming in 100g of solution,

Mass of NaCl = 16.2 g

Volume = mass/density

= 16.2/81.9

= 0.198 l of NaCl solution is needed.

answer is: nuclear fusion produces elements that are heavier than helium.

nuclei combine to form a heavier nucleus, releasing energy.  

for example, fusion of hydrogen atoms at the sun.  

this fusion nuclear reaction is in the inner core of the sun and hydrogen (atomic number 1) is conveted into helium (atomic number 2).  

the inner core is the central region of the sun and all solar energy is produced in the core by nuclear fusion.