If I have an unknown quantity of gas at a pressure of 1.2 atm, a volume of 77 liters, and a temperature of

Express 345.6 in scientific notation

Gnom [1K]

3.456 x 10^2 is the answer you're looking for.

6 0

3 years ago

Which of these statements describes a chemical property

sp2606 [1]

Sugar burns in air describes a chemical property

<h3>Further explanation </h3>

In the matter of a substance, there is a process of change.

2 changes occur in the mater, namely: physical changes and chemical changes

Classification uses the principle of the initial and final state of the substance.

Physical changes are changes in the matter which in the process do not cause new substances. So the properties of the particles remain the same.

Generally, the physical changes that occur are changes in shape / size and changes due to heating, or changes in volume

Example:

melting

a solid changes to a liquid

freezing

a liquid changes to a solid

boiling

a solid changes to a liquid

Chemical changes are changes in the process that produce new substances that are different from the initial / forming substances. Chemical changes are usually known as chemical reactions. So there are products / reactions and reactants

So in chemical changes, there is a change in the molecule / particle

From this we can know the physical and chemical properties of a substance

physical properties:

melting point, viscosity, ductile, freezing point, boiling point, density, odor, solubilty, turbidity, color etc.

chemical properties:

Highly flammable, corroded, explosive, toxic etc.

Let's look at the answer choices in the attached picture

1. water boils at 100 C

physical properties of water that is boiling point

2. mercury is liquid at room temperature

physical properties: the form of substances

3. Helium is the lightest monoatomic element

physical properties: the weight or mass of a substance

4. sugar burns in water to form water and carbon dioxide

chemical properties: the formation of new substances

<h3>Learn more </h3>

an example of a physical change

brainly.com/question/1119909

example of a chemical change brainly.com/question/9388643

examples of chemical changes brainly.com/question/11189422

7 0

3 years ago

Read 2 more answers

Label each statement below as either describing the limit of detection (LOD) or the limit of quantitation (LOQ

Orlov [11]

Answer:

It is the minimum amount of analyte that produces a signal which can be measured with reasonable accuracy - LOQ

The concentration is equal to three times the standard deviation of the signal from the blank divided by the slope of the calibration curve - LOD

The concentration is equal to 10 times the standard deviation of the signal from the blank divided by the slope of the calibration curve - LOQ

It is the minimum amount of analyte that produces a signal that is significantly different from the blank - LOD

Explanation:

We define the limit of detection has the lowest amount of analyte that produces a signal that is significantly different from a blank solution ( the absence of the substance). It is calculated as three times the standard deviation of the signal from the blank divided by the slope of the calibration curve.

The limit of quantitation (LOQ) is defined as the minimum amount of analyte that produces a signal which can be measured with reasonable accuracy. It is measured as 10 times the standard deviation of the signal from the blank divided by the slope of the calibration curve.

6 0

3 years ago

What is the compound of libr

Katarina [22]

Answer:

Lithium Bromide

Explanation:

3 0

3 years ago

• Define and describe in detail (and in your own words) ultrasound and infrasound

qaws [65]

Answer:

Human ears can hear sound waves that vibrate in the range from about 20 times a second (a deep rumbling noise) to about 20,000 times a second (a high-pitched whistling). (Children can generally hear higher-pitched sounds than their parents, because our ability to hear high frequencies gets worse as we get older.) Speaking more scientifically, we could say that the sounds we can perceive have a frequency ranging from 20–20,000 hertz (Hz). A hertz is a measurement of how often something vibrates and 1 Hz is equal to one vibration each second. The human voice makes sounds ranging from a few hundred hertz to a few thousand hertz.

Suppose you could somehow hit a drum-skin so often that it vibrated more than 20,000 times per second. You might be able to see the skin vibrating (just), but you certainly couldn't hear it. No matter how hard you hit the drum, you wouldn't hear a sound. The drum would still be transmitting sound waves, but your ears wouldn't be able to recognize them. Bats, dogs, dolphins, and moths might well hear them, however. Sounds this like, with frequencies beyond the range of human hearing, are examples of ultrasound.

Infrasonics, vibrational or stress waves in elastic media, having a frequency below those of sound waves that can be detected by the human ear—i.e., below 20 hertz. The range of frequencies extends down to geologic vibrations that complete one cycle in 100 seconds or longer.

4 0

3 years ago