Question

the work function for platinum is about 6.3 ev. what is the energy in joules for the work function?
1ev = 1.602 × 10⁻¹⁹ j
wₚₜ = ? × 10^? j

Explanation:

Step1: Use unit conversion factor

We know $1\ \text{eV} = 1.602 \times 10^{-19}\ \text{J}$, so multiply the work function in eV by this conversion factor.
$6.3\ \text{eV} \times 1.602 \times 10^{-19}\ \frac{\text{J}}{\text{eV}}$

Step2: Calculate the numerical value

First compute $6.3 \times 1.602 = 10.0926$. Then adjust to scientific notation.
$10.0926 \times 10^{-19}\ \text{J} = 1.00926 \times 10^{-18}\ \text{J}$

Step3: Round to reasonable precision

Round to two significant figures (matching 6.3 eV).
$1.0 \times 10^{-18}\ \text{J}$ (or $1.01 \times 10^{-18}\ \text{J}$ for more precision)

Answer:

$1.0 \times 10^{-18}\ \text{J}$ (or $1.01 \times 10^{-18}\ \text{J}$)