Answer:
it will have 1 valence electron as its in the first group in the periodic table.
It will lose electrons as its easier.
The charge will be 1+ as it lost 1 .
Explanation:
It is given that two loads have 0.75 Ampere current each. And, they contain 2500 milli ampere per hour Ni-Cd battery.
As both the loads are connected in parallel. Hence, total current will be calculated as follows.
I = 
= 0.75 A + 0.75 A
= 1.5 A
= 
= 1500 mA
Relation between time and capacity of battery is as follows.
Capacity = Current × time (in hour)
therefore, time = 
= 
= 1.667 hr
Thus, we can conclude that the battery provide power to the load up to 1.667 hours.
Answer:
Sodium (Na)
Explanation:
The element on the periodic table at Column (group) 1, period 3 is Sodium (Na)
1) You need to use the atomic mass of copper.
You can find it in a periodic table. It is 63.546 amu.
2) The atomic mass is the weigthed mass of the different isotopes.
This is, the atomic mass of one element is the atomic mass of each isotope times its corresponding abundance:
=> atomic mass of the element = abundance isotope 1 * atomic mass isotope 1 + abundance isotope 2 * atomic mass isotope 2 + ....+abundance isotope n * atomic mass isotope n.
3) The statement tells there are two isotopes so the abundance of one is x and the abundance of the other is 1 - x
=> 63.546 amu = x * 62.9296 amu + (1-x)*64.9278
=> 63.546 = 62.9296x + 64.9278 - 64.9278x
=> 64.9278x - 62.9296 = 64.9278 - 63.546
=> 1.9982x = 1.3818
=> x = 1.3818 / 1.9982 = 0.6915 = 69.15%
=> 1 - x = 1 - 0.6915 = 0.3085 = 30.85%
Answer:
Cu-63 69.15%;
Cu-65 : 30.85%
NaHCO3 is the right answer
