Предмет: Химия, автор: Аноним

Карбонат кальция массой 10г обработали избытком соляной кислоты . Образовавшийся газ пропустили через раствор известковой воды . Вычислите массу полученного осадка !

Ответы

Автор ответа: Аноним

Дано:
m(CaCO₃)=10г
m₂(CaCO₃)-?

Решение:
СaCO₃ + 2HCl = CaCl₂ + H₂O + CO₂
CO₂ + Ca(OH)₂ = CaCO₃ + H₂O

по реакции 1:
n(CaCO₃)=10г 100гмоль =0,1 моль
n(CO₂)=n(CaCO₃)=0,1 моль

по реакции 2:
n(CaCO₃)=n(CO₂)=0,1 моль
m₂(CaCO₃)=0,1 моль* 100 гмоль =10г
Ответ: 10г

Предыдущий вопрос

Следующий вопрос

Похожие вопросы

Предмет: Биология, автор: gogolya38svyaznoy

Почему растение растёт биология?

7 лет назад

Предмет: Английский язык, автор: AshleyMiller

n the world of running shoes, the trend has been toward more cushion, more support, more comfort. But, to a small group of running coaches and foot specialists, modern athletic shoes are doing to feet what plush living room sofas and TV remotes have been doing to people: making them lazy, physically underdeveloped and more prone to injuries.

A few years ago when Nike was looking for the next big advance in running shoe design, they asked some of the world's most respected track and field coaches for advice. A common response must have made their heads spin a little: We do not need any more shoe, we need less shoe, in fact, maybe we need no shoe. Give us the bare human foot.

Legendary Stanford track coach Vin Lananna said, "I believe that athletes that have been training barefoot run faster and have fewer injuries. It's just common sense ". Vin regularly put his athletes through their paces barefoot on the grass of the university's practice golf course. Other coaches agree, and point to the foot / ankle strength and resistance to injury seen in African and Caribbean runners who have grown up playing and running barefoot much of the time.

So, the research and development team at Nike set out to make a shoe that acted like it was not there; one that trained and worked the foot as nature intended. What's the point, you may ask? Why not just train in your bare feet? Well, that's fine if you have a finely groomed golf course to run on, but most athletes train in the street, in the gym, on the track, or out on the trails. This still calls for a shoe that not only offers protection from glass and pebbles, but also from the strike of the foot on hard bruising surfaces.

The first step was to measure exactly what happened to the bare foot when it ran: what the contact areas were between the foot and the ground, how the ankle and toes moved. Once they collected the data, the next step was to create a shoe that could reproduce the natural foot movement. The design team, led by Toby Hatfield and Eric Evar, struggled through innumerable concepts and finally came up with an entirely new kind of shoe. Deep slices in the sole, virtually no ankle support and room for the toes to spread out and move; all head-turning designs. Then it was off to testing again, to make sure the shoe really imitated barefoot running. There was a lot of "back to the drawing board" fine tuning but eventually the Nike Free was created and ready for real-world testing.

Earlier this year, in Germany at the University of Cologne the results of a season-long research study of university track athletes showed enhanced performance and speed by training in the Nike Free shoes. One key point is that Nike Free is a "training shoe," and Nike Free and barefoot training are tools to make you stronger.
1. How did Nike designers 'react to the experts "advice?

A. They were enthusiastic.

В. They were confused.

C. They were skeptical.

D. They were set against.

2. According to Vin Lananna, which of the following explains the need for a shoe that could reproduce the barefoot movement?
A. Training barefoot is just common sense.

В. It was a request by the design team at Nike .

C. The traditional sneakers design was on the way out.

D. Training barefoot improves runners "stamina.

3. Why can not modern athletes just train in bare feet?

A. They do not see the point.

В. They are used to shoes.

C. They may get injured.

D. They have not thought of it.

4. The word 'head-turning "(designs) in the text is closest in meaning to

A. attractive

В. sophisticated

C. breakthrough

D incredible

5. By mentioning "back to the drawing board" fme tuning "the author means that the Nike designers

.

A. used the drawings of the previous models

В. had to start the procedures all over again

C. made a lot of drawings before fme tuning

D. tested their new concept back and forth

7 лет назад

Предмет: Алгебра, автор: 87057402840az

найдите значение коэффициета К,если известно что график функции y=k/x переходит точку со координатами А(-1;-5)

7 лет назад

Предмет: Физика, автор: гульч

Напишите пожалуйста мини сочинение на тему: ,,Что могло бы случиться если не было гравитации"

10 лет назад

Предмет: Физика, автор: Vivilka

Приведите примеры потребления энергии на производстве, на транспорте, в системах связи, торговле, городском хозяйстве, при создании интеллектуальной продукции, в быту

10 лет назад