Ratios and Rates

What is the mechanical advantage of this gear ratio?

• Torque Advantage

• Speed Advantage

• no Mechanical Advantage

Tags

NGSS.MS-PS2-2

How is a gear ratio written?

• 
• # of Teeth of the Driving Grear / # of Teeth of the Driven Gear

Tags

NGSS.MS-PS2-2

A 36 tooth driving gear (connected to the motor) is moving a 12 tooth driven gear. What is the gear ratio?... It has a speed advantage.

• 3:1

• 1:3

• 3:3

• 1:1

What is the mechanical advantage of this gear ratio?

• Torque Advantage

• Speed Advantage

• no Mechanical Advantage

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2

A formula with the lowest whole # ratio of elements in a compound is called

• Molecular Formula

• Chemical Formula

• Empirical Formula 

• Distance Formula

An empirical formula:

• is a formula that calculates the coefficients of a compound in a balanced equation.

• is the simplest whole-number ratio of moles of elements in the compound.

Find the empirical formula for a compound which contains 32.8% chromium and 67.2% chlorine.

• CrCl

• CrCl₃

• Cr₃Cl

• Cr₂Cl₆

A compound containing 92.3 percent carbon and 7.7 percent hydrogen. What is the empirical formula?

• CH

• CH₂

• C₂H

• C₂H₂

Calculate the number of atoms in 0.0340 g Zn.

• 5.200 x 10^-4 atoms Zn

• 3.130 x 10²³ atoms Zn

• 3.130 x 10²⁰ atoms Zn

• 1 atom Zn

Tags

NGSS.HS-PS1-7

In a chemical reaction, the rate of reaction is often expressed as a ratio. Which of the following best describes this ratio?

• A) The ratio of reactants to products over time

• B) The ratio of the concentration of reactants to the concentration of products

• C) The ratio of the change in concentration of reactants to the change in concentration of products over time

• D) The ratio of the volume of reactants to the volume of products

Tags

NGSS.HS-PS1-5