So since every 20 mins the mass will be cut in half (and that happens 3 times), you have just got to divide 1g by 2, 3 times.
after 20 mins the mass will be .5
after 40 mins the mass will be .25
Answer: After 1 hour the mass will be .125g
Answer:
b. Bakelite
Explanation:
Bakelite -
Bakelite is a form if plastic , and is the very first plastic synthesized .
The handles of the cooking utensils are used to hold the utensil firmly , and hence need not turn hot while cooking , and need to be strong enough to take care of the food .
Hence , the handle should be of the material which is poor conductor of heat and strong .
Hence , bakelite is used for making the handle.
CaCI2 is for calcium chloride
Explanation:
When we move across a period from left to right then there will occur an increase in electronegativity and also there will occur an increase in non-metallic character of the elements.
As calcium (Ca) is a group 2A element and rubidium (Rb) is a group 1A element. Hence, Rb being an alkali metal is more metallic in nature than calcium (alkaline earth metal).
Both magnesium (Mg) and radium (Ra) are group 2A elements. And, when we move down a group then as the size of element increases so, it becomes easy of the metal atom to lose an electron.
As a result, there occurs an increase in metallic character of the element. Hence, Radium (Ra) is more metallic in nature than magnesium (Mg).
Also, both bromine and iodine are group 17 elements. Since, both of them are non-metals and non-metallic character increases on moving down the group.
Therefore, bromine (Br) is more metallic than iodine.
