Answer:
![Q=1.04kJ](https://tex.z-dn.net/?f=Q%3D1.04kJ)
Explanation:
Hello,
In this case, for latent heat (phase change) we need to consider the enthalpy associated with the involved process, here, melting or fusion; thus, the enthalpy of fusion of copper is 13.2 kJ/mol, therefore, the heat is computed as:
![Q=m\Delta H_{fus}](https://tex.z-dn.net/?f=Q%3Dm%5CDelta%20H_%7Bfus%7D)
Nevertheless, since the given enthalpy is per mole of copper, we need to use its atomic mass to perform the correct calculation as follows:
![Q=5.0g*\frac{1mol}{63.54}* 13.2\frac{kJ}{mol}\\ \\Q=1.04kJ](https://tex.z-dn.net/?f=Q%3D5.0g%2A%5Cfrac%7B1mol%7D%7B63.54%7D%2A%2013.2%5Cfrac%7BkJ%7D%7Bmol%7D%5C%5C%20%5C%5CQ%3D1.04kJ)
Which is positive as it needs to be supplied to the system.
Best regards.
The density of ice is less than the density of water.
Fun fact: Water is the only known liquid that has this change it density.
Let us assume that there is a 100g sample of Opal. The masses of each element will be:
29.2g Si
33.3g O
37.5g H2O
Now we divide each constituent's mass by its Mr to get the moles present
Si: (29.2 / 28) = 1.04
O: (33.3 / 16) = 2.08
H2O: (37.5 / 18) = 2.08
Now we divide by the smallest number and obtain:
Si: 1
O: 2
H2O: 2
Thus, the empirical formula of Opal is:
SiO2 . 2H2O
Answer:
2.73
Explanation:
2.72815277835894
i used an online converter lol it is much faster. if you'd like a step by step guide comment and ill give you one :)
It is (CI) bromine
because, <span>Halogen element, any of the six nonmetallic elements that constitute Group 17 (Group VIIa) of the periodic table. The halogen elements are </span>fluorine (F)<span>, </span>chlorine (Cl), bromine (Br<span>), iodine (I), astatine (At), and tennessine (Ts).</span>