I am having trouble balancing my adjusted trial balance.

I'm not sure I am posting to the correct accounts.

1. Services provided but unbilled and uncollected at July 31 were $1,700

My answer:

1700 AR
1700 Revenue

Is this correct?

2. Depreciation on equipment for the month was $180.

My answer:

180 Depreciation expense
180 Accumulated depreciation expense

3. One-twelfth of the insurance expired----Insurance for the year was $1,800

My answer:

$150 Insurance expense
$150 Prepaid Insurance

4. An inventory count shows $320 of cleaning supplies on hand at July 31. 900 of cleaning supplies were purchased on account.

My answer:

580 supplies expense
580 supplies
5. Accrued but unpaid employee salaries $400

My answer

400 salaries expense
400 salaries payable.

Your answers are correct except Accumulated Deprecreciation is not an expense account. It is a contra asset account.