Which property of an atom's structure was used to organize the periodic table?

What effect would you expect this to have on CO2 levels in the atmosphere?

VLD [36.1K]

expect what to have?!?!?!?

5 0

2 years ago

Which of the following electron configurations describes an element that is a noble gas?

butalik [34]

Answer:

The answer to your question is: letter D.

Explanation:

Noble gases are located in group VIIIA of the periodic table, this means that they have 8 eight electrons in their outermost shell.

Due to this characteristic, they are stable and do not react with other elements.

a. 1s22s22p4 The outermost shell of this electron configuration has 6 electrons, then this element has 6 electrons not 8. This configuration is of an element of the group VIA.

b. [Ne]2s22p2 The outermost shell of this element has 4 electrons, so this is not the configuration of a noble gas.

c. [Ar] 3s1 This element only has one electron in its outermost shell, so this is the electron configuration of an alkaline metal.

d. 1s22s22p6 This element has 8 electrons in its outermost shell, so this is the electron configuration of a noble gas.

5 0

3 years ago

Read 2 more answers

What are some examples of supersaturated solutions? Give 10.

Phantasy [73]

Examples include carbonated water (i.e. soda water); honey; sugar syrup (used in confectionery); supersaturated drug delivery systems. "SDDS"; and sodium acetate solutions prepared from 160 g NaOAc and 30 mL water.

7 0

3 years ago

Here is a more complex redox reaction involving the dichromate ion in acidic solution: 3N O 2 − + 8H + + C r 2 O 7 2− → 3N O 3 −

Fantom [35]

Answer:

NO2- is the reducing agent.

Cr2O7_2- is the oxidizing agent.

H+ is neither

Explanation:

Reduction is the gain in electron. A chemical specie that undergoes reduction is called the oxidizing agent.

Oxidation is simply the loss in electrons. A chemical specie that undergoes oxidation is called the reducing agent.

Let us look at the species.

The first specie is the NO2-. In this specie, the oxidation number of nitrogen changed from +3 to +5 in NO3-. Thus we can see that there is more loss of electron to have caused an increase in the oxidation number positively. This shows an oxidation. Hence, NO2- is the reducing agent.

Let us look at the chromium. We can see that the oxidation number of chromium changed from +7 to +3.

Now we can see that it is a decrease and hence, it is a gain of electron and thus it is reduction. This means the first chromium specie is the oxidizing agent.

The hydrogen ion is simply placed there to balance the ions and hence it is neither the oxidizing nor the reducing agent.

4 0

3 years ago

Epinephrine (adrenaline) is a hormone secreted into the bloodstream in times of stress. It contains 59.0% C, 7.15% H, 26.20% O,

vichka [17]

Answer:

C9H13O3N

Explanation:

Take the atomic mass of C=12.0, H=1.0, O=16.0 and N=14.0.

We can draw a chart (please view this on desktop so to avoid spacing errors):

Let the mass of Epinephrine be 100g.

C H O N

mass(g) : 59 7.15 26.2 7.65

no. of moles : 59/12 =4.9167 7.15/1 = 7.15 26.2/16=1.6375 7.65/14=0.5464

(n.o.m. = mass/molar mass)

Ratio: 4.9167/0.5464 =9 7.15/0.5464=13 1.6375= 3 0.5464/0.5464 =1

(divide the n.o.m. by the smallest n.o.m., which is 0.5464 in this case, take the whole numbers)

So, the empirical formula will be: C9H13O3N

But this is still not yet the molecular formula. We have to ensure the molar mass is 183g/mol. Multiply the empirical formula by n.

So, let the molecular formula of Epinephrine be (C9H13O3N)n.

12x9n + 1x13n + 16x3n + 14n = 183

108n + 13n + 48n + 14n = 183

183 n = 183.

n = 1

Hence, the molecular formula is C9H13O3N.

3 0

3 years ago