The smallest mass is that of ………….. Of the order of …………… kg.

Answer

To solve the question regarding the smallest mass and its order, we can follow these steps:

### Step 1: Identify the smallest particle
The smallest known particle in terms of mass is the electron.

### Step 2: Find the mass of the electron
The mass of an electron is approximately \(9.1 \times 10^{-31}\) kg.

### Step 3: Express the mass in a suitable form
To express the mass in a more manageable form, we can rewrite \(9.1 \times 10^{-31}\) kg as \(0.91 \times 10^{-30}\) kg.

### Step 4: Determine the order of the mass
The order of the mass of the electron can be determined by looking at the exponent in the scientific notation. In this case, the order is \(10^{-30}\) kg.

### Final Answer
Thus, the smallest mass is that of the electron, of the order of \(10^{-30}\) kg.

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