What is the mass percent of aluminum in al(oh)3 the molar mass of al = 26.98, h = 1.0079, and o = 16.00

34.58%

Explanation:-

Mass percentage is the ratio of mass of a particular element present in the total mass of the substance in terms of percentage.

Given: mass of AL = 26.98, H = 1.0079, and O = 16.00

Thus mass of

Putting the values in the equation:

Thus mass percent of aluminum in is 34.58%.

answer : third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

explanation :

let us write down the given equations

equation 1 :

equation 2 :

equation 3 :

let us use hess's law to find out which 2 equations can be added to get the third equation.

let us reverse equation 2 and multiply it by 2. the new equation that we get is,

equation 4 :

let us add equation 1 & 4

the above equation is similar to equation 3 but has different value for dhrxn.

therefore third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol