Answer:
5
Explanation:
A lithium atom with an atomic number of 3 and a charge of -2 will have a total number of electrons.
The atomic number is the number of protons in an atom. For a neutral atom that has not gained or lost electrons, the atomic number is the same as the number of electrons.
neutral atom: atomic number of electrons
For neutral atom of lithium, we will have 3 electrons
Now, lithium with a charge of -2 has gained two more electrons to the original 3 this now makes it 5.
ii.
It is an anion because it is negatively charged.
Negatively charged particles are called anion.
Answer:9.18 m/s
Explanation:
The average speed for the entire trip is found ......total distance/total time. Remember r*t=d, so divide both sides by t and get r = d/t.
So the cyclist went 800+500+1200 m = 2500 m for total distance.
10t =800 leads to t=80 sec
5t=500 leads to t=100 sec
13t = 1200 leads to t = 92.3 sec
total time is 272.3 sec
Average speed for the entire trip is 2500 / 272.3 = 9.18 m/s
The tubes 1, 5 and 6 is the answer to the question which test tubes were used to determine the optimal ph lipase activity. Lipase is an enzyme and optimum ph the maximum possible point on which enzyme become active.
Answer:
Oil has the smaller heat capacity. The effectiveness of the heat exchanger is 0.80.
Explanation:
Part 1:
In order to know which fluid has the smaller heat capacity we need to consider the heat equation below:
Q = CΔT, where Q is the heat exchanged, C is the heat capacity and ΔT is the variation in temperature.
As the heat exchange is the same for both fluids, the smaller the temperature variation, the smaller the heat capacity.
Water: ΔT = 120 °F
Oil: ΔT = 80 °F
Therefore, oil is the fluid with the smallest heat capacity.
Part 2:
The effectiveness of a counter-flow heat exchanger is given by the equation bellow:
Th1: initial temperature of the hot fluid
Th2: final temperature of the hot
Tc1: initial temperature of the cold fluid
Answer: amount of substance n = cV = 2.0 mol/l x 0.25 l = 0.50 mol
Explanation:
