题干

某化学反应过程的微观示意图如图,下列说法错误的是(   )

A:原子是化学变化中的最小粒子

B:元素的种类、原子的数目在化学反应前后不变

C:在化学变化中分子分成原子,原子又重新组合成新物质的分子

D:上述反应的化学方程式可表示为:2A+B=A2B

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D

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How to enroll if you are in Midhaven…

    We invite you to visit us and see the school. After an assessment you will be able to reserve a place on the next available course. We have two centres in Midhaven.

Deposits/payment

1). Your enrolment form must be accompanied by the course deposit of £100 or, if you are booking accommodation through the school, your course and accommodation deposit of £200.

2). Any balance of course and accommodation fees must be paid in full by the first day of your course.

3). All bank charges incurred (承受) in sending money to Ashwood College must be paid by the student.

4). Deposits and payments are non-refundable and non-transferable.

5). A charge of £20 will be made for any changes made to bookings.

Conditions

Timetable

Each hour consists of 50 minutes' tuition and a 10-minute break.

Public and School Holidays

There is no reduction in the fee where a course includes a Public Holiday, except for two weeks at Christmas.

Age

The above centres of Ashwood College do not accept students under 16 years of age.

Attendance

Students are expected to attend regularly and on time. Students will lose tuition if they arrive late, are absent or leave before the course ends.


Student Holidays

Students on long courses except examination preparation courses may take a holiday of one week every 12 weeks without losing their course fee for this period.

Location and Time of Courses

Ashwood College has two all-year centres and a summer centre in Midhaven. Before entry to the school, students must take an entry test to determine the level of class they enter. We cannot guarantee the time or location of a student's course although every attempt is made to place students in the centre and at the time of their choice.