# Given that the atomic radius of silver is #145*"pm"#, how many silver atoms will span a length of #4.70*mm#?

##### 1 Answer

Sep 6, 2017

In effect they are asking how many lengths of

#### Explanation:

Now we can do this dimensionally......

Why did I double the given radius? Did I make an error?

We note that

And that

The rest is arithmetic. Of course, we have to do the ratio properly. I have never found it straightforward.