Answer:
A
Explanation:
a heterogeneous mixture is one that is not uniform in composition.It is made up of non-uniform mix of smaller constituent parts that could be separated from one another using various means.
Answer:
[OH-] = 6.17 *10^-10
Explanation:
Step 1: Data given
pOH = 9.21
Step 2: Calculate [OH-]
pOH = -log [OH-] = 9.21
[OH-] = 10^-9.21
[OH-] = 6.17 *10^-10
Step 3: Check if it's correct
pOH + pH = 14
[H+]*[OH-] = 10^-14
pH = 14 - 9.21 = 4.79
[H+] = 10^-4.79
[H+] = 1.62 *10^-5
6.17 * 10^-10 * 1.62 * 10^-5 = 1* 10^-14
Answer: The empirical formula is 
Explanation:
Mass of Pb = 4.33 g
Mass of O = (5.00-4.33) g = 0.67 g
Step 1 : convert given masses into moles
Moles of Pb =
Moles of O =
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For Pb = 
For O = 
The ratio of Pb O= 1: 2
Hence the empirical formula is 
Answer:
70.1 mL
Explanation:
First let's look at the formula for magnesium nitrate, and get the molar mass, we should end up with Mg(NO3)2 for the formula and this should have a molar mass of 148.3 g/mol.
Lets get the number of moles of the magnesium by taking the number of grams over the molar mass, (21.94 g)/(148.3 g/mol). grams cancel and we're left with approximately 0.148 moles.
Now let's plug our numbers into the molarity formula, M = n/L, this should give us 2.11 mol/L = (0.148 mol)/L, now let's solve for L, divide both sides by 0.148 which will give us 14.26 L^-1 = 1/L now we take the inverse of both sides to get 0.07012 L = L.
Now we have the liters, but the question askes for milliliters, so let's multiply by 1000, and then after rounding to sig figs we will get 70.1 mL as our answer. (Note: I used the exact values instead of the approximations throughout this explanation, so if you calculate the answer by plugging in these values, it might be slightly off.)