Korean traveller in Russia heading to China, Question about Visa

Hi, I'm korean and want to travel through Russia, Mogolei and Peking to Korea.
Where can I apply for chinese visa in Russia? Just in Moskau? Because I read an article in internet that the foreigners can't get the entry permit at consulate in Irktusk, but only in Moskau, is it true?

And is it enough, if I show the flight ticket from Peking to Korea instead of round-ticket?

Thanks a lot!