Balances Review

Analytical balances weigh substances with a high degree of accuracy.

• True

• False

Match the following definitions:

• Scale is at zero mark after pan added

• True

• Scale is at zero mark before pan added

• Taring

• balance at rest and scale reads zero

• Zeroing

Two pans of equal mass are suspended from ends of a lever or beam and calibrated weights are placed on one pan to counterbalance an object of unknown mass on the other pan. This is known as a:

• Mechanical Analytical Balance

• Electronic Analytical Balance

• Top Loading Balance

• Triple Beam Balance

A top loading balance is usually ______ and ______.

• Electronic, self-balancing

• Mechanical, manual-balancing

A balance that has moveable weights that lock into accurately milled notches at each calibration mark to ensure accuracy is known as a:

• Mechanical Analytical Balance

• Top Loading Balance

• Triple Beam Balance

• Electronic Analytical

Match the following parts of an analytical balance:

• pans are suspended from this

• Glass Enclosure

• give sensitivity to the balance

• Beam

• prevents air currents and dust

• Knife edges

• used for leveling the balance

• Balancing Screws

When handling balances:

• Hot objects may be weighed directly on the pan

• Chemicals may be weighed directly on the pan

• 50-100g is a safe limit for most balances

• Fingerprints don't affect balancing

When using a balance, precision may be sacrificed for speed.

• True

• False

What kind of balance is this?

• Electronic Analytical Balance

• Top Loading Balance

• Triple Beam Balance

• Mechanical Analytical Balance

Corrosive materials should be weighed in a closed container or on a top loading balance.

• True

• False