Calculate the percent errors for Student C’s trials.

$$\begin{matrix} \text{ } & \text{Density} & \ {Error (g/cm^3 )}\\ \text{Trial 1} & \ {1.70 \mathrm{g} / \mathrm{cm}^{3}} & \text{ +0.11}\\ \text{Trial 2} & \ {1.69 \mathrm{g} / \mathrm{cm}^{3}} & \text{ +0.10}\\ \text{Trial 3} & \ {1.71 \mathrm{g} / \mathrm{cm}^{3}} & \text{ +0.12}\\ \text{Average} & \ {1.70 \mathrm{g} / \mathrm{cm}^{3}} & \text{ }\\ \end{matrix}$$

Dina calculated given of the following mentally:
$49\cdot 51 + 49\cdot 49 = 4900$
$98\cdot 37 + 2\cdot 37 = 3700$
$99\cdot 37 + 37 = 3700$
Explain how she performed the calculations and why her method works. Then give three similar calculations based on the same approach and find the answers mentally.

The speedometer displays a car’s speed in miles per hour. What is the car’s speed in km/h? (1 km = 0.62 mile)

Write each element’s orbital notation and complete electron configuration. sodium

What is the electron configuration for a neutral atom of nitrogen?

What conversion factors are needed to convert: a. nanometers to meters? b. density given in $\mathrm{g} / \mathrm{cm}^{3}$ to a value in $\mathrm{kg} / \mathrm{m}^{3}$?

What is the electron configuration for aluminum?

What conversion factors are needed to convert: nanometers to meters?

Write two conversion factors for each of the following. a. a 16% (by mass) salt solution b. a density of 1.25 g/mL c. a speed of 25 m/s

Write each element's orbital notation and complete electron configuration. A. beryllium B. aluminum C. nitrogen D. sodium

Vinegar is 5% acetic acid by mass and has a density of 1.02 g/mL. What mass of acetic acid, in grams, is present in 185 mL of vinegar?

Write two conversion factors for each of the following. a 16% (by mass) salt solution

Write the conversion factors needed to determine the number of seconds in one year.

Draw electron dot diagrams for oxygen, potassium, iodine, nitrogen, and beryllium.