Answer:
I think is d.
Explanation:
particles that make up the nucleus are balanced. An atom is unstable (radioactive) if these forces are unbalanced; if the nucleus has an excess of internal energy. the Instability of an atom's nucleus may result from an excess of either neutrons or protons.
I'm not sure, but hope it helps.
Answer:
The new volume is 5.913*10^4 L
Explanation:
Step 1: Write out the formula to be used:
Using general gas equation;
P1V1 / T1 =P2V2 /T2
V2 = P1V1T2 / P2T1
Step 2: write out the values given and convert to standard unit's where necessary
P1 = 0.995atm
P2 0.720atm
V1 = 5*10^4 L
T1 = 32°C = 32+ 273 = 305K
T2 = -12°C = -12 + 273 = 261K
Step 3: Equate your values and do the calculation:
V2 = 0.995 * 5*10^4 * 261 / 0.720 * 305
V2 = 1298.475 * 10^4 / 219.6
V2 = 5.913 * 10^4 L
So the new volume of the balloon is 5.913*10^4 L
Molarity is defined as the number of moles of solute in 1 L of solution
number of NaOH moles present - 0.20 mol
volume of solution - 150 mL
since molarity is taken as number moles of solute in 1000 mL
if 150 mL contains - 0.20 mol
then 1000 mL should contain - 0.20 / 150 x 1000 = 1.33 mol
therefore molarity is 1.33 M
Answer: A) grinding coffee beans
Explanation:
A physical change is defined as a change in which there is alteration in shape, size etc. No new substance gets formed in these reactions.
A chemical change is defined as a change in which a change in chemical composition takes place. A new substance is formed in these reactions.
1. Grinding coffee : Only change in size takes place, thus a physical change
2. Baking a cake: the chemical reaction occurs by combination of flour with oxygen , thus a chemical change.
3.:converting water to hydrogen and oxygen: The decomposition iof water takes place, thus is a chemical change
4.Burning of coal: the chemical reaction occurs by combination of carbon with oxygen , thus a chemical change.
