Answer:
There are 188.96 gm of moles in NaF
Answer:
Explanation:
Unclear question.
I infer you want a clear rendering, which reads;
A 258.4 g sample of ethanol (C2H5OH) was burned in a calorimetric pump using a Dewar glass. As a consequence, the water temperature rose to 4.20 ° C.
If the heat capacity of the water and the surrounding glass was 10.4 kJ / ° C, calculate the heat of combustion of one mole of ethanol.
The correct is tricky, be careful. The right is silicon dioxyde (SiO2)
Silicon Oxides are written in the form SiOx, (0 <x <2), so:
there is no silicon trioxygen and disilicon dioxygen.
SiO is called silicon monoxide and not monosiicon oxygen, so this proposition is false.
All that remains is the silicon dioxide (SiO2) that is written correctly.
Silicon dioxide can be synthesized but also exists in abundance in nature. Silicon (Si) represents about 26% of the Earth's crust. Silica (SiO2), the natural form of silicon dioxide, accounts for about 60%.
Answer:
C. The half-life of C-14 is about 40,000 years.
Explanation:
The only false statement from the options is that the half-life of C-14 is 40,000yrs.
The half-life of an isotope is the time it takes for half of a radioactive material to decay to half of its original amount. C-14 has an half-life of 5730yrs. This implies that during every 5730yrs, C-14 will reduce to half of its initial amount.
- All living organisms contain both stable C-12 and the unstable isotope of C-14
- The lower the C-14 compared to the C-12 ratio in an organism, the older it is.
