根据短文内容，判断对错。
One day an American dentist was starting his morning work. Suddenly a man ran in. His face was
red and he could only say, "Quick! Quick!" The dentist though the must be very ill. His assistant (助手)
helped to make the man sit in a chair. The dentist gave the man some medicine to make him sleep. Then
he looked into the man's mouth and pulled out all the bad teeth. After the man woke up, he said in a low
voice, "Quick, doctor! Quick!"
"It's all right now. "the dentist told him. "It's over!"
"You don't understand(理解). " said the man. "I came to tell you your house is on fire (火).
( )1. The man is ill.
( )2. The dentist is a Canadian.
( )3. The man's house is on fire.
( )4. The dentist pulled the man's bad teeth.
( )5. The dentist didn't understand the man at first (起初).
，恰好恢复到电解前的pH和浓度，则电解过程中转移的电子的物质的量为：