Answer:
76
Explanation:
128 is the mass number. it means protons+nutrons=128
then the atomic number of te-128 is 52. atomic number means the number of protons .
so 128-52=76.
if you don't get it, I'll explain it later
Answer: The new pressure of the gas, assuming that no gas escaped during the experiment is 0.470 atm
Explanation:
Combined gas law is the combination of Boyle's law, Charles's law and Gay-Lussac's law.
The combined gas equation is,
where,
= initial pressure of gas = 0.732 atm
= final pressure of gas = ?
= initial volume of gas = 6.87 L
= final volume of gas = 9.22 L
= initial temperature of gas = 
= final temperature of gas = 
Now put all the given values in the above equation, we get:
Thus the new pressure of the gas, assuming that no gas escaped during the experiment is 0.470 atm
Sink. This is because the density (mass divided by volume) is greater than that of water, and anything that has a greater density than water sinks while anything with a lower density than water floats. Hope this helps.
Answer: In essence, Boyle defined alkalies as substances that consume, or neutralize, acids. Acids lose their characteristic sour taste and ability to dissolve metals when they are mixed with alkalies. Alkalies even reverse the change in color that occurs when litmus comes in contact with an acid.
Explanation:
Amount of copper= mass / molar mass = 17/64=0.2656
According to the balance equation, amount of hydrogen gas : amount of copper = 1:1
Therefore amount of hydrogen gas is 1:1
Thus mass of hydrogen gas is molar mass x mol= 1 x 0.2656= 0.266g
