如图是氯元素、钠元素在周期表中的位置及相关的结构示意图，据图回答下列问题：

氯元素的原子序数为____ 　；钠元素的相对原子质量为　____ 　；属于氯原子的结构示意图是____ （填序号）；氯原子的电子层数为____ 　层；钠元素与氯元素形成化合物的化学式为　____ ．

有关澳大利亚的说法，错误的是（　　）

阅读理解

You Can Make a Windsock(风筒)

    Have you ever seen a windsock blowing in the wind? Well, you can make one of your own! This is a fun project that you can do with things you may have. You just need to follow a few easy steps.

You will need:

●one piece of heavy colored paper   ●five ribbons

●strong tape       ●a string

●a pencil

What to do:

Step 1: Draw pictures on the paper. You can write your name on it. Do anything that will make it special to you.

    Step 2: Make the paper into the shape of a tube. Hold one of the shorter edges(边缘) over the other. Then make them together with the tape at each end and in the middle.

Step 3: Use a pencil to make a hole into both sides of the tube. The holes should be only on one end of the tube. Pull the string through both holes. Then tie the ends of the string together.

    Step 4: Now make five holes around the top of the other end of the tube.Put a ribbon through each of the holes. Tie a knot in the ends.

    Make sure the knots are bigger than the holes.

    Now your windsock is ready to use, but how does it work? The shape of the tube plays an important part. Wind blows through the tube and makes it fly and dance around. Hold the windsock up in the air by its string and run around. It will fly behind you. You can also hang it outside and watch it dance around on its own!