All categories

3 years ago

1. Antoine Lavoisier, a French scientist, established which principle?

Chemistry

1 answer:

pickupchik [31]3 years ago

6 0

Answer: The correct option is d.

Explanation: Antoine Lavoisier is a french scientist who discovered the role of oxygen in the process of combustion and respiration.

He was famous for the law of conservation of mass.

This law states that the total mass the reactant will equal to the total mass of the products in a chemical reaction.

For example: Combustion of methane

$CH_4+2O_2\rightarrow CO_2+2H_2O$

Mass of the reactants = $[12+4(1)]+[2(32)]=80g/mol$

Mass of the products = $[12+2(16)]+2[2(1)+16]=80g/mol$

Hence, every chemical reaction will follow law of conservation of mass.

You might be interested in

A substance's particles are in constant, random motion.

Leona [35]

Answer:

D. Kinetic energy and is present in all states of matter.

Step-by-step explanation:

According to Kinetic Molecular Theory, all particles of matter are in constant, random motion.

The energy of this motion is kinetic energy.

6 0

3 years ago

Read 2 more answers

Why are non-metals dull in appearance as solids?

Inessa [10]

Metalloids are metallic-looking brittle solids that are either semiconductors or exist in semiconducting forms, and have amphoteric or weakly acidic oxides. Typical nonmetals have a dull, coloured or colourless appearance; are brittle when solid; are poor conductors of heat and electricity; and have acidic oxides.

6 0

4 years ago

3. The light given off by an electric discharge through sodium vapor is

Fittoniya [83]

Answer:

An emission spectrum.

Explanation:

An element's emission spectrum is the intensity of the electromagnetic radiation of each frequency emitted by the atoms of that element during excitation. In the case of sodium vapor, when the vapor is excited by an applied voltage or an electric force or field, the atoms in the vapor emits a light spectrum.

6 0

4 years ago

Read 2 more answers

Draw the Lewis structure for methane (CH4) and ethane (C2H6) in the box below. Then predict which would have the higher boiling

Alinara [238K]

Answer:

Ethane would have a higher boiling point.

Explanation:

In this case, for the lewis structures, we have to keep in mind that all atoms must have 8 electrons (except hydrogen). Additionally, each carbon would have 4 valence electrons, with this in mind, for methane we have to put the hydrogens around the carbon, and with this structure, we will have 8 electrons for the carbon. In ethane, we will have a bond between the carbons, therefore we have to put three hydrogens around each carbon to obtain 8 electrons for each carbon.

Now, the main difference between methane and ethane is an additional carbon. In ethane, we have an additional carbon, therefore due to this additional carbon, we will have more area of interaction for ethane. If we have more area of interaction we have to give more energy to the molecule to convert from liquid to gas, so, the ethane will have a higher boiling point.

I hope it helps!

7 0

3 years ago

What is the mass of a sample of iron if that sample lost 2300J of heat energy when it cooled from 80 oC to 30°C? The specific he

irakobra [83]

102 grams.
Equation:
Quantify of heat = mass x specific heat x difference in temperature
We have: quantity of heat : 2300J
specific heat: .449 J/g
difference in t: 80 - 30 = 50
Solve for mass: 2300 = mass x 0.449 x 50
mass = 102.449
2 sig-figs --> 102 grams

7 0

3 years ago