Câu 2:

Phương trình chữ:

Carbon Dioxide + Calcium Hydroxide → Calcium Carbonate + Nước

Phương trình hóa học:

CO₂ + Ca(OH)₂ → CaCO₃ + H₂O

Câu 3:

a.

(+) Phương trình chữ:

        Aluminium + Oxygen (t^o)→ Aluminium oxide

     Phương trình hóa học:

        Al + O (t^o)→ Al₂O₃

(+) Ta có:

Al + O (t^o)→ Al₂O₃

=> mAl + mO = m_Al2O3

=> 10.8 + mO = 15 

=> mO=15-10.8=4.2 (g)

There are lots of people in the big city

How do you spend your weekends?

How much time you spend surfing the net a day?

After school, we usually hang out together by have a bike ride around the city. Then, we go to some snack shop near our school for some breaktime snacks and drinks. Next, we go to a small stadium near the school to watch some of my classmates having a football match with other classes and have fun with them, especially Dung, he's a very good football player in my class. After that, we spend time with each other to talk about things that happened in the days. It so fun, and we also can connect with each other to raise up our relationship.

There are many dirts on the floor → There is much dirt on the floor

My hand is decaying: Bàn tay của tôi đang trở nên mục nát!

To reduce his laptop's energy, he decided to set his laptop to hybernating mode

Vì tổng số hạt trong nguyên tử là 155, nên:

 \(p+n+e=155\)

Vì số hạt \(p\) và \(e\) là bằng nhau nên:

\(2p+n=155\)

Vì số hạt mang điện (\(p\&e\)) nhiều hơn số hạt không mang điện \(\left(n\right)\) là 33 hạt, nên:

\(2p-33=n\)

Ta có:

- Số hạt \(p\) và \(e\) là:

\(\dfrac{\left(155+33\right)}{2}\div2=47\)

- Số hạt \(n\) là:

\(155-47\cdot2=61\)

Vậy: 

- Số hạt \(p,e,n\) là: \(47;47;61\)