题干

小明将50g的盐完全溶解在如图乙所示的量筒内的水中,水面升高后的位置如图丙所示,则盐水的密度是多少?

上一题 下一题 0.0难度 选择题 更新时间:2019-12-11 10:05:00

答案(点此获取答案解析)

解:此题要根据水的体积与水的密度求出量筒内水的质量,用水的质量加上食盐的质量等于食盐水的质量.观测食盐溶解后量筒内液体的体积,用食盐水的质量除以其体积就得出其密度.m=50g
mv=1g/cm3×40cm3=40g
v盐水=60cm3
ρ盐水=

同类题4



Monday

8—10 a. m

TECHNOLOGYInformation Technology (IT )—Using the Internet

In this lesson, students learn how to surf the internet safely and effectively. There will also be information about using different search engines. Finally, this lesson teaches students about the best websites to use to continue their education online.

10—12 a. m

ARTS

10:00 a. m

DRAMA

Students learn the play that the teacher gave before class. During this lesson, students will have the chance to act out roles with other students.

11:00 a. m

PAINTING WITH WATERCOLOURS

For most of this term, students learn how to use watercolours properly to make pictures. If the weather is good, the lesson may take place outdoors.


LUNCH

1—2 p. m

SCIENCES Biology/Chemistry

Students can choose which class to attend

In biology this week, the topic is Human Body. Students will learn about how it works.

Alternatively, students can study chemistry. This class takes place in the science lab, and this week students learn about H2and O2

2—4 p. m

SPORTS

2:00 p. m

SIKLLS

Students learn about the skills in a certain sport. We use video to see real action from past games.

3:00 p. m

PRACTICE

After we have picked teams, students will play a short match lasting 45 minutes. This week, the sports are football(for boys) and tennis (for girls)


HOMEWORK

IT— the teacher will give students websites to look up at home (about 30minutes)

Drama –students have to learn a part for the next lesson (about 40 minutes)

Biology/ Chemistry—students have to write a short report of the lesson (about 20 minutes)