Answer:
A. The identify of the poison used in a murder.
Explanation:
Answer:
molecular diagram 3 or 2 is correct answer I hope it helps you
The mass of 1.72 mol of magnesium fluoride is 107 grams.
To determine the mass of 1.72 mol of magnesium fluoride, we first need the chemical formula of magnesium fluoride. Magnesium forms a +2 ion (Mg+2) and fluoride forms a -1 ion (F-1). Since all compounds formed from ions have to be electrically neutral, we need 2 fluoride ions and 1 magnesium ion. Therefore, the formula for magnesium fluoride is MgF2.
Now we need to determine the molar mass of the compound from the molar mass values from the periodic table. Let's use a table to calculate this molar mass.
Molar mass of MgF2
Element Molar Mass (g/mol) Quantity Total (g/mol)
Mg 24.31 1 24.31
F 19.00 2 38.00
Total molar mass of MgF2 = 24.31 g/mol + 38.00 g/mol = 62.31 g/mol
This is the mass of one mole of the substance. If we have 1.72 mols of it, we multiply 1.72 by 62.31.
1.72 mol (62.31 g/mol) = 107 grams
We rounded to 107 to keep the correct number of significant digits in our answer.
each isotope of a given element has a different mass number. For example, carbon-12, carbon-13<span> and carbon-</span>14<span> are </span>three<span> isotopes of the element carbon with mass numbers </span>12<span>, </span>13<span> and </span>14<span> </span>
Answer: The rate increases 3 times on raising the temperature from 20degree to 30 degree
Explanation:
According to Arrhenius equation with change in temperature, the formula is as follows.
![ln \frac{k_{2}}{k_{1}} = \frac{-E_{a}}{R}[\frac{1}{T_{2}} - \frac{1}{T_{1}}]](https://tex.z-dn.net/?f=ln%20%5Cfrac%7Bk_%7B2%7D%7D%7Bk_%7B1%7D%7D%20%3D%20%5Cfrac%7B-E_%7Ba%7D%7D%7BR%7D%5B%5Cfrac%7B1%7D%7BT_%7B2%7D%7D%20-%20%5Cfrac%7B1%7D%7BT_%7B1%7D%7D%5D)
where 
= rate constant at temp 
= rate constant at temp 
= activation energy
R= gas constant
= temperature = 
= temperature = 
![ln \frac{k_{2}}{k_{1}} = \frac{-85\times 1000J/mol}{8.314J/Kmol}[\frac{1}{303} - \frac{1}{293}]](https://tex.z-dn.net/?f=ln%20%5Cfrac%7Bk_%7B2%7D%7D%7Bk_%7B1%7D%7D%20%3D%20%5Cfrac%7B-85%5Ctimes%201000J%2Fmol%7D%7B8.314J%2FKmol%7D%5B%5Cfrac%7B1%7D%7B303%7D%20-%20%5Cfrac%7B1%7D%7B293%7D%5D)
Thus rate increases 3 times on raising the temperature from 20degree to 30 degree
