Fireworks
An exothermic reaction is one where the products have lower energy than the reactants, so the reaction yields energy. The chemical compounds present in firework fuel release a lot of energy upon oxidation. Photosynthesis is endothermic, settling of silt is not a chemical reaction, it is a physical change. Finally, the bubble formation in soda is not exothermic; otherwise, the sodas would become very hot very fast.
Answer:
The element from Group 13.
Explanation:
Following trends of the periodic table, atomic radius of the elements increase going down from the right side and decrease on its way up diagonally to the left. (sry if u can't understand me)
I think it’s A good luck on the answer if it’s not but I’m pretty sure it’s A .
Answer:
TRIAL 1:
For “Event 0”, put 100 pennies in a large plastic or cardboard container.
For “Event 1”, shake the container 10 times. This represents a radioactive decay event.
Open the lid. Remove all the pennies that have turned up tails. Record the number removed.
Record the number of radioactive pennies remaining.
For “Event 2”, replace the lid and repeat steps 2 to 4.
Repeat for Events 3, 4, 5 … until no pennies remain in the container.
TRIAL 2:
Repeat Trial 1, starting anew with 100 pennies.
Calculate for each event the average number of radioactive pennies that remain after shaking.
Plot the average number of radioactive pennies after shaking vs. the Event Number. Start with Event 0, when all the pennies are radioactive. Estimate the half-life — the number of events required for half of the pennies to decay.
Explanation: