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3 years ago

I need help with this science!

Chemistry

2 answers:

o-na [289]3 years ago

6 0

Answer:

Scientists classify living things at eight different levels: domain, kingdom, phylum, class, order, family, genus, and species. In order to do this, they look at characteristics, such as their appearance, reproduction, and movement, to name a few.

Explanation:

Eddi Din [679]3 years ago

3 0

Answer:

All living organisms share several key characteristics or functions: order, sensitivity or response to the environment, reproduction, growth and development, regulation, homeostasis, and energy processing. When viewed together, these characteristics serve to define life.

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. Which law of motion relates the action of a stretched rubber band

storchak [24]

Answer:

newtons 3rd law of motion

Explanation:

3 0

3 years ago

A salt solution will conduct electricity but if sugar solution will not explain why

Rainbow [258]

Salt solution such as sodium chloride (NaCl) conducts an electric current because it has ions in it that have the freedom to move about in solution. ... On the other hand, sugar solution does not conduct an electric current because sugar (C12H22O11) dissolves in water to produce sugar molecules

6 0

3 years ago

if 0.0203 g of a gas dissolves in 1.39 l of water at 1.02 atmospheres at what pressure (in atm) would you be able to dissolve 0.

Sergeu [11.5K]

First, we need to get n1 (no.of moles of water ): when

mass of water = 0.0203 g and the volume = 1.39 L

∴ n1 = mass / molar mass of water

= 0.0203g / 18 g/mol
= 0.00113 moles

then we need to get n2 (no of moles of water) after the mass has changed:

when the mass of water = 0.146 g

n2 = mass / molar mass

= 0.146g / 18 g/ mol
= 0.008 moles

so by using the ideal gas formula and when the volume is not changed:

So, P1/n1 = P2/n2

when we have P1 = 1.02 atm

and n1= 0.00113 moles

and n2 = 0.008 moles

so we solve for P2 and get the pressure

∴P2 = P1*n2 / n1

=1.02 atm *0.008 moles / 0.00113 moles

= 7.22 atm

∴the new pressure will be 7.22 atm

5 0

3 years ago

Draw a lewis structure for ketene, c2h2o, which has a carbon–carbon double bond

MrMuchimi

Visual representation of covalent bonding indicating the valence shell electrons in the molecule, lines represents the shared pair of electron and pair of electrons that are not involved in bonding are represented as dots(lone pairs) are known as Lewis structures.

Compound formation takes place in order to complete the octet of each element that is according to octet rule, each atom forms bond with other atom in order to complete their octet that is to get eight electrons in its valence shell and attain stability.

An organic compound of the form $R^{'}R^{''}C=C=O$ is known as ketene.

The given ketene is $C_2H_2O$ .

The number of valence electron of:

$C = 4$

$H = 1$

$O = 6$

The number of valence electrons in $C_2H_2O$ = $2\times 4+2\times 1+1\times 6 =16$

2 electrons are involved in each single bond between carbon and hydrogen and 4 electrons are involved in each double bond formed between carbon-carbon and carbon-oxygen. Hence, the total number of electrons involved in bond formation are 12 and rest 2 pair of electrons are present on oxygen as lone pair of electrons.

Therefore, the attached image is the Lewis structure of $C_2H_2O$ .

8 0

3 years ago

Which atom, selenium (Se) or Arsenic (As), has the higher electron affinity and why?

IrinaVladis [17]

Answer:

5. Selenium, because it does not have a stable, half-filled p subshell and adding an electron does not decrease its stability.

Explanation:

Electron affinity is the amount of energy released when an isolated gaseous atom accepts electron to form the corresponding anion.

Selenium:-

The electronic configuration of the element is:-

$[Ar]3d^{10}4s^24p^4$

Arsenic:-

The electronic configuration of the element is:-

$[Ar]3d^{10}4s^24p^3$

The 4p orbital in case of arsenic is half filled which makes the element having more stability as compared to selenium.

Thus, selenium has higher electron affinity because adding electron does not decrease the stability as in case of arsenic.

8 0

3 years ago