1. Is an appointment required for a visa application? Can I entrust someone else to apply for me?
No appointment is required. You may entrust someone else or a travel/visa agent to come to the visa office for application process, but mail visa applications are not acceptable.

2. Can I provide the embassy or consulate with a photocopy of my passport for visa application?
No. You must provide your actual passport.

3. My child is traveling to China with me. He cannot sign his name on his application; can I sign it on his/her behalf?
Yes. The parents/guardian are allowed to sign the application form instead of the child.

4. I can't download your application form from the Internet, Can you e-mail me one?
We can't e-mail it to you. Please give us your fax number and we can fax one to you.

5. I'm going to China on June 1, and my visa will expire on June 10. Can I still stay in China for 30 days?
Yes. Usually, a Chinese visa is good for 90 days from the date of issuance, you can enter China any day Within the 90 days (please note the time difference between China and the U.S.); Duration of stay of a visa is usually 30 days (It is written in the visa label), you can stay in China for 30 days from the date of your entrance.

6. Do I have to see a doctor to have the " Physical examination record for foreigner" filled out?
This form is strictly for those who will study in China over 1 year. If you are to stay in China for less than one year, you don't have to see a doctor to fill it out.

7. I am going to Guangdong, then to Hongkong and back to Guangdong for one night. Does it mean that I must have a double-entry visa?
Absolutely. Double-entry visa means you can enter into mainland of China twice. Since you are going to Guangdong twice, you must have a double-entry visa.
8. Can I use a certified envelope to mail my application to your office?
No problem. You can choose any envelope to mail your application to us. What we really care about is the return mail. We would like to advise you to use FedEx or Express Mail, because they are traceable.

The Chinese Embassy and Consulates take authentication applications sent by mail, but do not take visa applications sent by mail.

9. I am wondering whether you have received my application. Can I call you to check the status of my application?
Please don't call us for the status of your application processing unless you haven't received your application after 15 days of submission. In case of emergency, you are encouraged to fax us the name of the applicant, and the telephone number through which we may reach you. We'll answer you as soon as possible.

10. My return mail would be USPS Priority Mail. Do you have any idea how much postage I should pay?
Please check postage with the post office. As we know, the postage depends on the weight of the package. For FedEx user, write down your FedEx account number or your credit card number on the airbill and the delivery company will charge your account. We would like to advise you to use FedEx or Express Mail,because they are traceable.

11. I try to call your office, but it is very difficult to reach you.
We receive about 300 calls from different states each day. We have a person answering phone calls all day . If you have a question to which you can't find the answer on the website, you can e-mail or fax it to us. We'll call you back as soon as possible.

Source: http://www.china-embassy.org/eng/hzqz/faqv/t170583.htm