题目

Mark and his brother Jason both were looking at the shining new computer enviously．Jason was determined not to go against their father's wishes but Mark was more adventurous than his brother．He loved experimenting and his aim was to become a scientist like  his father.“Dad will be really mad if he finds out you've been playing with his new computer.”Jason said，“He told us not to touch it.”“He won't find out，” Mark said，“I'll just have a quick look and shut it down.”Mark had been scolded before for touching his father's equipment．But his curiosity was diff有5.1g Mg、Al合金投入500mL 1mol/L HCl中，金属完全溶解后，又加入2mol/LNaOH溶液V mL，得最多沉淀8.6g。则V等于（　） 　　A. 425 　　B. 560 　　C.250 　　D.500