Carbon-14 and Uranium-238 have something we call a half live, which is basically a known time period for it to change half of its C-14 or U-238 radioactively decay. Since we know how long that is 5730 years for Carbon-14 for half a sample to deteriorate, than we can figure out how old it is.
Answer:
The answer is
<h2>26.94 g/mL</h2>Explanation:
The density of a substance can be found by using the formula
From the question
mass = 970 g
volume = 36 mL
The density of the object is
We have the final answer as
<h3>26.94 g/mL</h3>Hope this helps you
Answer: 4.18925 kJ heat is needed to convert 25.0 g of solid ethanol at -135 °C to liquid ethanol at -50°C.
Explanation:
Temperature of Solid
Melting temperature of Solid
Temperature of liquid
Specific heats of solid ethanol = 0.97 J/gK
Specific heats of liquid ethanol = 2.3 J/gK
Heat required to melt the the 25 g solid at 159 K
= 159 K - 138 K = 21 K
Heat required to melt and raise the temperature of upto 223 K
= 223 K - 159 K = 64 K
Total heat to convert solid ethanol to liquid ethanol at given temperature :
(1kJ=1000J)
Hence, 4.18925 kJ of heat will be required to convert 25.0 g of solid ethanol at -135 °C to liquid ethanol at -50°C.