Answer:
2621.75 j heat is required to increase the temperature 25.5°C to 46°C.
Explanation:
Given data:
Mass of sample = 142.1 g
Initial temperature = 25.5°C
Final temperature = 46°C
Specific heat capacity of Al = 0.90 J/g.°C
Solution:
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 46°C - 25.5°C
ΔT = 20.5°C
Q = 142.1 × 0.90 J/g.°C × 20.5°C
Q = 2621.75 j
Thus, 2621.75 j heat is required to increase the temperature 25.5°C to 46°C.
One half times one half is .25 or 25%
Answer:
The element potassium(K) with atomic number 19 has the largest atomic radius ( around 225 picometers ).
Explanation:
There is the general expected decrease from left to right with increasing nuclear charge without quantum level expansion or increase in shielding and so pulling the outer electrons closer. The 3d block of metals (Z = 21 to 30) tend to be similar and in fact tend to go through a small minimum at Mn/Fe.
The potassium been on the left most part of period , has largest radius due to least nuclear pulling effect.
This question is dealing with the half-life of carbon-14 which can be used to determine the age of a substance according to the following equation:
t = [ln(N/No)/(-ln2)] · t1/2
N = # of carbon-14 atoms presently = 250 atoms
No = # of carbon-14 atoms initially = 1000 atoms
t1/2 = half-life = 5730 years for carbon-14
We can now input all of the information into the formula to find the age of the fossil:
t = [ln (250/1000)/-ln2] x 5730 years
t = 11460 years
The fossil should be found to be roughly 11,460 years old.
Answer:
3
Explanation:
litres is the appropriate unit to be used
