A certain metal hydroxide, M(OH)2 contains 32.8% oxygen by mass. What is the identity of the metal M? I don't understand what its asking for.

To determine the identity of the metal M in the metal hydroxide M(OH)2, we need to understand what percentage by mass means in the context of the compound.

Percentage by mass represents the proportion of a specific element's mass in the total mass of the compound. In this case, since we are given that oxygen (O) constitutes 32.8% by mass in M(OH)2, it means that for every 100 grams of M(OH)2, the mass of oxygen is 32.8 grams.

To find the identity of the metal M, we need to calculate the mass percentage of oxygen in M(OH)2 and then use that information to determine the mass percentage of the metal.

Here's how you can solve it step-by-step:

Step 1: Determine the molar mass of M(OH)2.
To calculate the molar mass, we need to sum the atomic masses of each element in the compound. The molar mass of oxygen (O) is approximately 16.00 grams/mol, and the molar mass of hydrogen (H) is approximately 1.01 grams/mol.

The molar mass of M(OH)2 = atomic mass of M + (2 * atomic mass of O) + (2 * atomic mass of H)

Step 2: Calculate the mass of oxygen.
Given that oxygen (O) represents 32.8% by mass in M(OH)2, we know that for every 100 grams of M(OH)2, there are 32.8 grams of oxygen.

Step 3: Calculate the mass of M.
Since we have the mass of oxygen in M(OH)2, subtracting that mass from the total mass of M(OH)2 will give us the mass of M.

Step 4: Calculate the percentage of M by mass.
To find the percentage by mass of M, we divide the mass of M by the total mass of M(OH)2 and multiply by 100.

By following these steps, we can determine the identity of the metal M in M(OH)2.

The question is asking you to determine the identity of the metal, indicated by the symbol M, in the metal hydroxide formula M(OH)2.

To solve this problem, you need to consider the percentage of oxygen in the compound. In M(OH)2, there are two moles of hydroxide ions (OH^-) for every mole of metal. Oxygen is present in the formula as part of the hydroxide ion.

Since oxygen is 16 grams per mole, and it makes up 32.8% of the compound's mass, we can set up the following equation:

32.8% oxygen = (2 * 16g) / total molar mass of the compound

To find the total molar mass of the compound, we need to consider the molar mass of oxygen and hydrogen and then multiply by the number of atoms in the compound:

Total molar mass = (2 * atomic mass of H) + atomic mass of M + (2 * atomic mass of O)

Now, we can substitute the known values into the equation and solve for M:

0.328 = (2 * 16g) / [(2 * (1g/mol)) + (molar mass of M) + (2 * 16g)]

Simplifying the equation further:
0.328 = 32g / (2 + molar mass of M + 32g)

Cross-multiplying, we get:
0.328 * (2 + molar mass of M + 32g) = 32g

0.656 + 0.328 * (molar mass of M) + 10.496 = 32g

0.328 * (molar mass of M) = 32g - 0.656 - 10.496

0.328 * (molar mass of M) = 20.848

Dividing both sides of the equation by 0.328, we get:
molar mass of M = 20.848 g / 0.328

Simplifying, we find:
molar mass of M ≈ 63.5g/mol

Using the periodic table, we can identify the metal M as having a molar mass of approximately 63.5 g/mol, which corresponds to copper (Cu). Therefore, the metal in the metal hydroxide M(OH)2 is copper.

You know the percent of O, so the percent of H is 1/16 of that, then you know the percent of M.

Knowing the percent of M, and the percent of 20's, you can determine the atomic mass of M.

MassatomicM/percentM=massatomic20/percentO

You know the atomic mass of M, and that it is in group II, you have....