Explanation:
chemical analysis of a compound shows that it contains 0.99g lead ,0.154g sulfur and 0.306g oxygen. what is the empirical formula of the compound.
Since there are 23 days and 24 hours in each day, you multi-ply them and get 552 hours. Since each hours is 60 minutes, 552*60 is 33120 minutes. Since one minute is 60 seconds, 60*33120 is 1,987,200 seconds. Therefore, there are 1,987,200 seconds in 23 days.
Answer: 
Explanation:
For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.
Here iron is having an oxidation state of +3 called as
cation and oxide
is an anion with oxidation state of -2. Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral
.
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.

Activation energy is the energy required by reactants to undergo chemical reaction and given products
Every reactant has some internal energy (sum of all kind of energy like kinetic energy, potential energy, mechanical energy, chemical energy etc). It needs some extra energy to undergo chemical reaction which is activation energy
All kinds of reaction whether exothermic or endothermic needs activation energy
Threshold energy = internal energy + activation energy
Answer:

Explanation:
Hello,
In this case, for this heat transfer process in which the heat lost by the hot platinum is gained by the cold deuterium oxide based on the equation:

We can represent the heats in terms of mass, heat capacities and temperatures:

Thus, we solve for the mass of platinum:

Next, by using the density of platinum we compute the volume:

Which computed in terms of the edge length is:

Therefore, the edge length turns out:
![a=\sqrt[3]{180cm^3}\\ \\a=5.65cm](https://tex.z-dn.net/?f=a%3D%5Csqrt%5B3%5D%7B180cm%5E3%7D%5C%5C%20%5C%5Ca%3D5.65cm)
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