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3 years ago

Which statement best describes evidence that a chemical reaction occurs as a cake bakes

Chemistry

2 answers:

ioda3 years ago

7 0

Answer: the cake rises as gas bubbles form in the cake

Explanation: Had a quizziz quiz on this

vekshin13 years ago

4 0

Answer: The cake rises as gas bubbles form in the baking cake.

Explanation: had a test, got it right.

You might be interested in

How many molecules are present in 2 H₂ SO4

fomenos

Answer:

in H2So4 splits in 2 H+ and a

so42 -particle=3particle per mole.So2

moles H2So4 will result in 3*2=6moles

of molecules.

5 0

2 years ago

Read 2 more answers

Once formed, how are coordinate covalent bonds different from other covalent bonds?

-Dominant- [34]

Answer:

$\boxed {\boxed {\sf {One \ atom \ donates \ both \ electrons \ in \ a \ pair}}}$

Explanation:

A covalent bond involves the sharing of electrons to make the atoms more stable, and so they satisfy the Octet Rule (8 valence electrons).

Typically each atom contributes an electron to form an electron pair. This is a single bond. There are also double bonds (two pairs of electrons), triple bonds (three pairs of electrons), and coordinate covalent bonds.

Sometimes, to satisfy the Octet Rule and achieve stability, one atom contributes both of the electrons in an electron pair. This is different from other covalent bonds because usually each of the 2 atoms contributes an electron to make a pair.

4 0

3 years ago

A student has a 2.19 L bottle that contains a mixture of O 2 , N 2 , and CO 2 with a total pressure of 5.57 bar at 298 K . She k

Sergeeva-Olga [200]

<u>Answer:</u> The partial pressure of oxygen gas is 2.76 bar

<u>Explanation:</u>

To calculate the number of moles, we use the equation given by ideal gas which follows:

$PV=nRT$

where,

P = pressure of the gas = 5.57 bar

V = Volume of the gas = 2.19 L

T = Temperature of the gas = 298 K

R = Gas constant = $0.0831\text{ L bar }mol^{-1}K^{-1}$

n = Total number of moles = ?

Putting values in above equation, we get:

$5.57bar\times 2.19L=n\times 0.0831\text{ L. bar }mol^{-1}K^{-1}\times 298K\\\\n=\frac{5.57\times 2.19}{0.0831\times 298}=0.493mol$

To calculate the mole fraction of carbon dioxide, we use the equation given by Raoult's law, which is:

$p_{A}=p_T\times \chi_{A}$ ........(1)

where,

$p_A$ = partial pressure of carbon dioxide = 0.318 bar

$p_T$ = total pressure = 5.57 bar

$\chi_A$ = mole fraction of carbon dioxide = ?

Putting values in above equation, we get:

$0.318bar=5.57bar\times \chi_{CO_2}\\\\\chi_{CO_2}=\frac{0.381}{5.57}=0.0571$

Mole fraction of a substance is given by:

$\chi_A=\frac{n_A}{n_A+n_B}$

We are given:

Moles of nitrogen gas = 0.221 moles

Mole fraction of nitrogen gas, $\chi_{N_2}=\frac{0.221}{0.493}=0.448$

Calculating the partial pressure of oxygen gas by using equation 1, we get:

Mole fraction of oxygen gas = (1 - 0.0571 - 0.448) = 0.4949

Total pressure of the system = 5.57 bar

Putting values in equation 1, we get:

$p_{O_2}=5.57bar\times 0.4949\\\\p_{O_2}=2.76bar$

Hence, the partial pressure of oxygen gas is 2.76 bar

6 0

3 years ago

Based on these ideas, what are the pro's and con's for both Sexual Reproduction and Asexual reproduction?

Svetradugi [14.3K]

Asexual
Pro:
1. inexpensive to make offspring (usually make a lot at a time and not invest a lot of time in raising them).
2. Do not need a mate to reproduce.
3. Can rapidly expand a population
Con:
1. genetically identical- prone to extinction because once a parasite has evolved to attack a specific genotype, it can kill them all.
2. Lineages usually don't last longer than a couple thousand years

Sexual:
Pros:
1. Genetically unique- so more likely to create a "successful" offspring
2. Lineages more likely to last hundreds of thousands of years

Cons:
1. More effort into creating offspring- require more parental effort
2. STD's- easily to pass
3. need to find a mate or else won't be successful as an organism.

Hope this helps you.

6 0

3 years ago

Calculate δs∘rxn for the reaction2no(g) o2(g)→2no2(g)express your answer to one decimal place and include the appropriate units

Anna35 [415]

The δs∘rxn for the reaction $2NO(g) + O_{2}$ → $2NO_{2} (g)$ will be -146 J/K.

Entropy would be a measurable physical characteristic and a scientific notion that is frequently connected to a condition of disorder, unpredictability, or uncertainty.

Entropy would be a measurement of the system's unpredictability or disorder. The entropy increases as randomness do. It has broad properties as well as a state function. It has the unit $JK^{-1} mol^{-1}$ .