The boiling point of liquid hydrogen is 20.2K . Express this is degree Rankine.

Explanation

To convert the boiling point of liquid hydrogen from Kelvin (K) to Rankine (°R), we can follow these steps:

### Step 1: Understand the conversion formula
The conversion from Kelvin to Rankine can be done using the formula:
\[ T°R = \left( T(K) \times \frac{9}{5} \right) \]

### Step 2: Substitute the given value
We are given that the boiling point of liquid hydrogen is:
\[ T(K) = 20.2 \, K \]

Now, substitute this value into the conversion formula:
\[ T°R = 20.2 \, K \times \frac{9}{5} \]

### Step 3: Calculate the Rankine temperature
Now, perform the multiplication:
\[ T°R = 20.2 \times 1.8 = 36.36 \]

### Step 4: Add the offset for Rankine
In the Rankine scale, we need to add 459.67 to the calculated value:
\[ T°R = 36.36 + 459.67 = 496.03 \, °R \]

### Final Answer
Thus, the boiling point of liquid hydrogen expressed in degrees Rankine is:
\[ T°R = 496.03 \, °R \]

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