Answer:
In my opinion testing with an experiment will be the most difficult when studying ancient creatures. You have to base off your research on fossils and might not be provided with accurate data depending on what your trying to prove or learn.
Explanation:
Each particular chemical reaction cannot be expected to occur at identical rates.
True. Not all chemical reactions happen at the same rate, depending on the catalyst.
Answer:
Balancing Nuclear Equations
To balance a nuclear equation, the mass number and atomic numbers of all particles on either side of the arrow must be equal.
Explanation:
follows:
6
3
Li
+
2
1
H
→
4
2
He
+
?
To balance the equation above for mass, charge, and mass number, the second nucleus on the right side must have atomic number 2 and mass number 4; it is therefore also helium-4. The complete equation therefore reads:
6
3
Li
+
2
1
H
→
4
2
He
+
4
2
He
Or, more simply:
6
3
Li
+
2
1
H
→
2
4
2
He
image
Lithium-6 plus deuterium gives two helium-4s.: The visual representation of the equation we used as an example.
Compact
Answer:
A. endothermic.
A. Yes, absorbed.
Explanation:
Let's consider the following thermochemical equation.
2 HgO(s) ⇒ 2 Hg(l) + O₂(g) ΔH = 182 kJ
The enthalpy of the reaction is positive (ΔH > 0), which means that the reaction is endothermic.
182 kJ are absorbed when 2 moles of HgO react (molar mass 216.59 g/mol). The heat absorbed when 72.8 g of HgO react is:
![72.8g.\frac{1mol}{216.59g} .\frac{182kJ}{2mol} =30.6kJ/mol](https://tex.z-dn.net/?f=72.8g.%5Cfrac%7B1mol%7D%7B216.59g%7D%20.%5Cfrac%7B182kJ%7D%7B2mol%7D%20%3D30.6kJ%2Fmol)