The collision of two plates causes the formation of fold mountains.
Answer:
= 72900 years
Explanation:
- The half-life is the time taken by a radioactive material to decay by half the original amount.
- The half-life of plutonium-239 is 24300 years which means it takes 24300 years to decay by half the original amount.
To calculate the time taken for a mass of 8 kg to decay to 1 kg we use;
New mass = Original mass x (1/2) ^n, where n is the number of half-lives
Therefore;
1 kg = 8 kg × (1/2)^n
1/8 = (1/2)^n
solving for n;
n =3
Therefore;
Time = 3 × 24300 years
= 72900 years
It will, therefore, take 72900 years for 8 kg of plutonium-239 to decay to 1 kg.
Answer:
chemical energy into thermal energy
Explanation:
The reaction taking place is as follows
2C₂H₂ + 5O₂ = 4CO₂ + 2H₂O + Heat
In this reaction bonds present in acetylene is broken and new bond present in water and carbon dioxide are formed . In the whole process of bond breaking and bond formation , there is net loss of energy and that energy is released as heat energy .
Thus we can say that in the whole process , chemical energy is converted into heat energy .
Answer:
1.14atm
Explanation:
Given parameters:
V1 = 250cm³ ;
1000cm³ = 1dm³; so this is 0.25dm³
P1 = 760torr
760torr = 1atm
V2 = 220cm³ ; 0.22dm³
Unknown:
New pressure = ?
Solution:
To solve this problem, we apply Boyle's law and we use the expression below:
P1 V1 = P2V2
The unknown is P2;
1 x 0.25 = P2 x 0.22
P2 = 1.14atm
Answer:
-
419kJ/mol
- 5,0,0,+12
- That catches fire spontaneously
Explanation:
1. Topic: Chemistry
ElementFirst Ionization Energy (kJ/mol) Lithium520Sodium496Rubidium403Cesium376According to the above table, which is most likely to be the first ionization energy for potassium?
2. Topic: Chemistry, Atom
The correct set of four quantum numbers for the valence electrons of the rubidium atom (Z=37) is:
3. Rubidium and cesium are pyrophoric. Here the term pyrophoric means:
- That does not catch fire at all
- That catches fire spontaneously
