If you mean the number of Significant Figures/Digits in 23.45, it would be 4. This is because every single non-zero digit is counted as a significant figure
The empirical formula is the same as the molecular formula : C₁₀H₅O₂
<h3>Further explanation</h3>
Given
Molecular formula : C₁₀H₅O₂
Required
The empirical formula
Solution
The empirical formula (EF) is the smallest comparison of atoms of compound forming elements.
The molecular formula (MF) is a formula that shows the number of atomic elements that make up a compound.
(empirical formula) n = molecular formula
<em>(EF)n=MF
</em>
(EF)n = C₁₀H₅O₂
If we divide by the number of moles of Oxygen (the smallest) which is 2 then the moles of Hydrogen will be a decimal number (not whole), which is 2.5, then the empirical formula is the same as the molecular formula
The chemical described above belongs to CLASS 1 EXPLOSIVES of DOT hazardous material classification. An hazardous substance is any substance which can cause adverse effects in humans when exposed to it. These substances are divided into different categories based on the way they react in different situations. It is mandatory that you aware of the kind of chemical you are working with when you are in the laboratory in order to take appropriate precautionary steps.
<u>Answer:</u> The initial concentration of hydrogen peroxide at the given temperature is 0.399 M
<u>Explanation:</u>
Decomposition of hydrogen peroxide is following first order kinetics.
Rate law expression for first order kinetics is given by the equation:
![k=\frac{2.303}{t}\log\frac{[A_o]}{[A]}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B2.303%7D%7Bt%7D%5Clog%5Cfrac%7B%5BA_o%5D%7D%7B%5BA%5D%7D)
where,
k = rate constant = 
t = time taken for decay process = 855 s
= initial amount of the reactant = ?
[A] = amount left after decay process = 0.321 M
Putting values in above equation, we get:
![2.54\times 10^{-4}s^{-1}=\frac{2.303}{855s}\log \frac{[A_o]}{0.321}](https://tex.z-dn.net/?f=2.54%5Ctimes%2010%5E%7B-4%7Ds%5E%7B-1%7D%3D%5Cfrac%7B2.303%7D%7B855s%7D%5Clog%20%5Cfrac%7B%5BA_o%5D%7D%7B0.321%7D)
![[A_o]=0.399M](https://tex.z-dn.net/?f=%5BA_o%5D%3D0.399M)
Hence, the initial concentration of hydrogen peroxide at the given temperature is 0.399 M
A <span>heating curve having horizontal plateaus at certain points during the heating process means that the process occurs at increase heating. </span>