Chemistry, 23.10.2021 14:00 owlsandR5

Which subatomic particle has a positive charge? Question 1 options:

all particles

neutron (n0)

proton (p+)

electron (e-)

Question 2 (2 points)
What information does the atomic mass of an element provide?

Question 2 options:

the difference between the number of protons and electrons (p - e)

the number of isotopes

the sum of electrons and protons in an atom (e + p)

the number of protons and neutrons in an atom (p + n)

Question 3 (2 points)
What is the atomic number of an atom?

Question 3 options:

the number protons and neutrons

the number of protons

the number of neutrons

the number of electrons and neutrons

Question 4 (2 points)
What is H2O (water) classified as?

Question 4 options:

a diatomic molecule

an atom

an element

a molecule

Question 5 (2 points)
Which property is a physical property?

Question 5 options:

easy to digest

becomes moldy quickly

does not burn

malleable (the quality of something that can be shaped into something else without breaking )

Question 6 (2 points)
What state of matter has a defined volume but undefined shape?

Question 6 options:

solids and liquids

liquids

liquids and gases

gases

Question 7 (2 points)
Which statement best describes the difference between a physical change and a chemical change?

Question 7 options:

A chemical change does not result in a new substance being formed, whereas a physical change does.

A chemical change results in a new element being formed, and a physical change results in a new compound being formed.

A physical change produces a new element, and a chemical change results in a bond breaking between atoms.

A physical change is a change from one state of matter to another; a chemical change results in a new substance formed.

Question 8 (2 points)
Where are nonmetals located in the periodic table?

Question 8 options:

in the middle

along the bottom

along the upper left side

along the upper right side

Question 9 (2 points)
The elements fluorine (F), chlorine (Cl), and Iodine are all part of the same on the periodic table.

Question 9 options:

period

group

Question 10 (2 points)
How are elements arranged on the periodic table?

Question 10 options:

atomic mass (# of protons and neutrons)

atomic number (# of protons)

density

boiling point

Help please ill give 100 points

Answers: 3

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Answers

Answer from: Quest

Ethene molecular fórmula= c2h4molecular weight = 29.046g/molhope it : )

Answer from: Quest

i think is conclusions.i think so

Answer from: Quest

Ireally don’t know bruh

Answer from: Quest

Note that 2 mol dm⁻³ = 2 mol/(dm³)outline: we're given the concentration of hcl, which is 2 mol dm⁻³ (cubic meters in the denominator can represent volume, so i know this is concentration). we're an amount of calcium carbonate caco₃, which is 5 g. we're presented with a chemical equation which includes caco₃ and hcl. we are told to find the volume of hcl. from what we see so far, this seems to be a stoichiometry problem. we'll have to use the given information about calcium carbonate to find the amount of moles of hcl needed to fully react with calcium carbonate. then we'll have information about the moles of hcl and the concentration of hcl; that will be enough to figure out volume according to the formula concentration = moles / volume.======all the answer choices are not in dm.convert the given concentration so that it uses cm⁻³.we can use conversion factors. we have to cube our conversion factors so that dimensional analysis works.we can convert to meters first, using the fact that 10 dm = 1 m ⇔ 10³ dm³ = 1 m³then we use the fact that 10² cm = 1 m ⇔ (10² cm)³ = (1 m)³ ⇔ 10⁶ cm³ = 1 m³so converting: $\dfrac{\text{2 mol}}{\text{dm}^{3}} \cdot \dfrac{\text{10}^3\text{ dm}^3}{\text{1 m}^3} \cdot \dfrac{\text{1 m}^3}{10^6\text{ cm}^3} \\ \\ = \dfrac{\text{2 mol}}{1} \cdot \dfrac{\text{10}^3}{1} \cdot \dfrac{1}{10^6\text{ cm}^3} \qquad \text{\footnotesize cancelling units} \\ \\ = \dfrac{2\text{ mol}}{10^3 \text{ cm}^3} \\ \\ = 0.002\text{ mol/cm}^3$ now we have to find the moles of hydrochloric acid neededfind the moles of calcium carbonate. we have to find the molar mass of calcium carbonate, caco₃, which can be found by molar mass = (mass ca) + (mass c) + 3(mass o) = 40 + 12 + 3(16) = 100 g/molconvert the given 5 g to moles: mol caco₃ = 5 g caco₃ * 1 mol/(100 g) = 0.05 mol caco₃use stoichiometry (ratios) to figure out the moles of hcl needed. ratio wise, there's 2 hcls for every caco₃, so use dimensional analysis mol hcl = mol caco₃ * (2 mol hcl) / (1 mol caco₃) = 0.05 mol hcl * 2 = 0.1 mol hcl we have 0.1 mol hcl and concentration of hcl (0.002 mol/cm³).we need to find volumesince concentration = moles / volume, rearrange to get volume = moles / concentration volume = 0.1 mol / (0.002 mol/cm³) volume = 50 cm³