Poor Brock Adams. He innocently showed up at your standard middle-of-the-week embassy reception last night, only to be surrounded by people who asked: "Are you out yet?"

But no, Jimmy Carter had not accepted the secretary of Transportation's resignation, offered en masse with 33 others from Cabinet members and top-level White House aides Tuesday.

The resignation fracas hadn't affected Adams, who with his wife Betty adopted a more or less high-on-life approach to the recent brouhaha. "I'm not worried in the least," isisted Adams, "I like my life." Said Betty Adams: "Never a dull moment."

Who is in and who might be out was without doubt the No. 1 conversation item at a goodbye party the Belgian Ambassador and Mrs. Van Cauwenberg gave for themselves at their Foxhall Road home. As a portion of some 500 invited guests hunched two and three deep over the bar and a liver pate shaped into an airplane, speculation was rampant on what the president might spring next.

But Chief Justice Warren Burger wasn't speculating, saying he was glad to be chief justice and not a Cabinet member. "I'm not going to be out," he chuckled, adding that he plans to stay "around for a while" because his office is being redecorated.

CIA Director Stansfield Turner was one of those who was speculating even though he claimed to know nothing. "No domestic spying going on," he explained.

As for other conversation beyond the we-re-going-to-miss-the-ambassador sort, a good many guests marveled at the Van Cauwenbergs' elegant home, modeled after the Hotel de Charolais in Paris and smelling of the flowers that were just about everywhere.

"I'm impressed," said Louis Balla, an 18-year-old who normally might have been at a movie with a bunch of his friends. The reason for his presence at a party filled with people old enough to have been his mother - or grandmother? "Escort service," he said, explaining that his dad was out of town, and his mom needed a date.

Speaking of dates, socialite Allison LaLand had a hard time finding hers. The problem was the bus shuttle, a service the Belgian ambassador and his wife had for guests forced to park their cars down the road near Mt. Vernon College. "I had a hard time catching it," said the date, John Gruver of Price, Waterhouse, who couldn't remember taking a bus to a party in his whole life.

As for the retiring Belgina ambassador, in whose honor the party was given: After five years on the job in Washington, soon he'll be back in Antwerp doing, he said, "as little as possible."

Incidentally, last night was also the ambassador's 65th birthday. He hates the thought of it.

"A birthday means you're a year older - right? he said. "What's there to celebrate about?" CAPTION: Picture, From left, Ambassador Van Cauwenberg, Nini Cauwenberg, Elvera Burger and Chief Justice Warren Burger; by Lucian Perkins