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3 years ago

Which of the following statements about atoms is NOT true?

Chemistry

1 answer:

Alika [10]3 years ago

6 0

Answer:

atoms are too small to be seen under a microscope

Explanation:

scientists have been always making research on atomic structure which cannot be directly looked through a microscope

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Gaseous butane will react with gaseous oxygen to produce gaseous carbon dioxide and gaseous water . Suppose 4.1 g of butane is m

m_a_m_a [10]

Answer:

12.44 g

Explanation:

2C4H10 + 13O2 = 8CO2 + 10H2O

n(C4H10) = m(C4H10)/M(C4H10) = 4.1 / 58g/mol = 0.0707 mol (excess).

n(O2) = m(O2)/M(O2) = 25.9 / 32g/mol = 0.809 mol (deficiency).

Since the ratio of O2 to octane is 13 : 2 we can divide 0.0707 by 2 to get 0.03535 and divide 0.809 by 13 to get 0.062.

mass of CO2 produced =

M = [0.0707 moles C4H10 x 8 moles CO2] / 2 moles C4H10 x 44 g CO2/mol

M = 0.5656/2 * 44

M = 0.2828 * 44

M = 12.44 of CO2

5 0

2 years ago

How many molecules are in 88g of carbon dioxide?

Volgvan

No of moles= 88/44 =2
therefore no. of molecules =

therefore no.of molecules= 12.046*10^23

8 0

3 years ago

Read 2 more answers

Calculate the number of ATPs generated by the complete metabolic oxidation of tripalmitin (tripalmitoylglycerol). Hydrolysis of

trapecia [35]

Answer:

Explanation:

412 ATP's will be generated from the complete metabolic oxidation of tripalmitin (tripalmitoylglycerol)

130 ATP from the oxidation of palmitate

22 ATP from the oxidation of glycerol

Altogether 130 + 22 = 412 ATP will be produced.

Here in case of tripalmitin (tripalmitoylglycerol), we have 51 carbons.

When 51 carbons can produce 412 ATPs

Then 1 carbon will produce how many ATPs = 412 ATPs/ 51 carbon= 8.1 ATPs.

This shows that ATP yield per carbon often oxidized will be 8.1 ATPs

Now we will see the ATP yield in the case of glucose.

Glucose is made up of 6 carbon and complete oxidation of glucose will produce 38 ATPs

When 6 carbons can yield 38 ATPs

Then 1 carbon can yield how many ATPs= 38 ATPs/ 6 carbons= 6.33 ATPs.

So, ATP yield per carbon in case of glucose will be 6.33 ATPs

8 0

3 years ago

The specific spatial arrangement of amino acid residues that are close to each other in the polypeptide chain is called______the

natulia [17]

Answer:

c. tertiary.

Explanation:

In this case, we can review the definition of each level of structuration in the proteins:

Primary structure

In the primary structure, the amino acids are linked by peptide bonds. That is, the order of the amino acids is the criterion that defines this type of structure.

Secondary structure

In the secondary structure, we have to look at the way in which the protein is folded. The options are:

-) Beta-laminar: A structure in which the protein has a planar shape.

-) Alpha-helix: A structure in which the protein has a cross-strand form.

Tertiary structure

In the tertiary structure, the R groups that the amino acids have in the primary structure can generate interactions with each other. Interactions such as hydrogen bridges, dipole-dipole, hydrophobic interactions. This makes the protein have a very specific three-dimensional structure, on which its function depends.

Quaternary structure

In the quaternary structure, several subunits may be attached, or there may be prostatic groups (metals that can help to attach various protein units).

With all these in mind, the deffinition that fits with the description in the question is the tertiary structure.

I hope it helps!

4 0

2 years ago

EXTRA POINTSSS 1. A solution at 25 degrees Celsius is 1.0 × 10–5 M H3O+. What is the concentration of OH– in this solution?

AlekseyPX

Answer:

Concentration of OH⁻:

1.0 × 10⁻⁹ M.

Explanation:

The following equilibrium goes on in aqueous solutions:

$\text{H}_2\text{O}\;(l)\rightleftharpoons \text{H}^{+}\;(aq) + \text{OH}^{-}\;(aq)$ .

The equilibrium constant for this reaction is called the self-ionization constant of water:

$K_w = [\text{H}^{+}]\cdot[\text{OH}^{-}]$ .

Note that water isn't part of this constant.

The value of $K_w$ at 25 °C is $10^{-14}$ . How to memorize this value?

The pH of pure water at 25 °C is 7.
$[\text{H}^{+}] = 10^{-\text{pH}} = 10^{-7}\;\text{mol}\cdot\text{dm}^{-3}$
However, $[\text{OH}^{-}] = [\text{H}^{+}]=10^{-7}\;\text{mol}\cdot\text{dm}^{-3}$ for pure water.
As a result, $K_w = [\text{H}^{+}] \cdot[\text{OH}^{-}] = (10^{-7})^{2} = 10^{-14}$ at 25 °C.

Back to this question. $[\text{H}^{+}]$ is given. 25 °C implies that $K_w = 10^{-14}$ . As a result,

$\displaystyle [\text{OH}^{-}] = \frac{K_w}{[\text{H}^{+}]} = \frac{10^{-14}}{1.0\times 10^{-5}} = 10^{-9} \;\text{mol}\cdot\text{dm}^{-3}$ .

8 0

3 years ago