What element with 26 electrons?

Assume the weight of an average adult is 70. kg, and that 420. kJ of heat are evolved per mole of oxygen consumed as a result of

seraphim [82]

Answer:

The temperature difference of the body after 3 hours = 5.16 K

Explanation:

we know that the number of moles of O₂ inhaled are 0.02 mole/min⁻¹

or, 1.2 mole.h⁻¹

The average heat evolved by the oxidation of foodstuffs is then:

⇒ Q avg = $\frac{1.2 X 420 X 10^{3} }{70}$ = 7.2 kj.h⁻¹.Kg⁻¹

the heat produced after 3 h would be:

= 7.2 kj. h⁻¹.Kg⁻¹ x 3 h

= 21.6 kj. kg⁻¹

= 21.6 x 10³ j kg⁻¹

We know Qp = Cp x ΔT

Assume the heat capacity of the body is 4.18 J g⁻¹K⁻¹

⇒ ΔT = $\frac{Qp}{Cp}$

⇒ ΔT = $\frac{(21.6 X 10^{3} j.kg^{-1} ) }{(4.18 j k^{-1}g^{-1}) X (1000g.kg^{-1} )}$

⇒ ΔT = 5.16 K

6 0

3 years ago

Sodium acetate can be formed from the metathesis/double replacement reaction of sodium

telo118 [61]

Answer:

Explanation:

Sodium Acetate Trihydrate BP Specifications

Sodium Acetate BP

C2H3NaO2,3H2O

Action and use

Used in solutions for dialysis; excipient.

DEFINITION

Sodium ethanoate trihydrate.

Content

99.0 per cent to 101.0 per cent (dried substance).

CHARACTERS

Appearance

Colourless crystals.

Solubility

Very soluble in water, soluble in ethanol (96 per cent).

IDENTIFICATION

A. 1 ml of solution S (see Tests) gives reaction (b) of acetates.

B. 1 ml of solution S gives reaction (a) of sodium.

C. Loss on drying (As shown in the Relevant Test).

TESTS

Solution S

Dissolve 10.0 g in carbon dioxide-free water prepared from distilled water R and dilute to 100 ml 100 ml with the same solvent.

Appearance of solution

Solution S is clear and colourless.

pH

7.5 to 9.0.

Dilute 5 ml of solution S to 10 ml with carbon dioxide-free water.

Reducing substances

Dissolve 5.0 g in 50 ml of water, then add 5 ml of dilute sulphuric acid and 0.5 ml of 0.002 M potassium permanganate. The pink colour persists for at least 1 h. Prepare a blank in the same manner but without the substance to be examined.

Chlorides

Maximum 200 ppm.

Sulphates

Maximum 200 ppm.

Aluminium

Maximum 0.2 ppm, if intended for use in the manufacture of dialysis solutions.

Arsenic

Maximum 2 ppm, determined on 0.5 g.

Calcium and magnesium

Maximum 50 ppm, calculated as Ca.

Heavy metals

Maximum 10 ppm.

Iron

Maximum 10 ppm, determined on 10 ml of solution S.

Loss on drying

39.0 per cent to 40.5 per cent, determined on 1.000 g by drying in an oven at 130C.

Sodium Acetate FCC Food Grade, US Food Chemical Codex

C2H3NaO2 Formula wt, anhydrous 82.03

C2H3NaO2·3H2O Formula wt, trihydrate 136.08

DESCRIPTION

Sodium Acetate occurs as colorless, transparent crystals or as a granular, crystalline or white powder. The anhydrous form is hygroscopic; the trihydrate effloresces in warm, dry air. One gram of the anhydrous form dissolves in about 2 mL of water; 1 g of the trihydrate dissolves in about 0.8 mL of water and in about 19 mL of alcohol.

Function: Buffer.

REQUIREMENTS

Identification: A 1:20 aqueous solution gives positive tests for Sodium and for Acetate.

Assay: Not less than 99.0% and not more than 101.0% of C2H3NaO2 after drying.

Alkalinity Anhydrous: Not more than 0.2%; Trihydrate: Not more than 0.05%.

Lead: Not more than 2 mg/kg.

Loss on Drying: Anhydrous: Not more than 1.0%; Trihydrate: Between 36.0% and 41.0%.

Potassium Compounds: Passes test.

5 0

3 years ago

harry potter flips a coin (not magical ) 8 times. He gets heads 1 time. What are the odds that his next flip will be heads? A 10

rodikova [14]

C. 50%
Unless the question is saying he only gets heads once, in which case it would be 0%. Or the coin could have 2 heads. Then it would be 100%.
But I'm pretty sure it's 50%.

7 0

2 years ago

Put the steps in process of photosythensis order

arlik [135]

Answer:

Step 1- CO2 and H2O enter the leaf.

Step 2- Light hits the pigment in the membrane of a thylakoid, splitting the H2O into O2.

Step 3- The electrons move down to enzymes.

Step 4-Sunlight hits the second pigment molecule allowing the enzymes to convert ADP to ATP and NADP+ gets converted to NADPH

Step 5-The ATP and NADPH is used by the calvin cycle as a power source for converting carbon dioxide from the atmosphere into simple sugar glucose.

Step 6-The calvin cycle converts 3CO2 molecules from the atmosphere to glucose

Step 7-calvin cycle. The second of two major stages in photosynthesis (following the light reactions), involving atmospheric CO2 fixation and reduction of the fixed carbon into carbohydrate.

Hope this helps : D

4 0

3 years ago

Which substances corrode copper?

DiKsa [7]

The presence of oxidizing acids; heavy-metal salts, sulfur, and ammonia; and a number of sulfur and ammonia compounds can cause corrosion to set in. Water that comes from a well is much more likely to contain these materials and put copper lines in jeopardy—but it can occur in the civic water system as well.

Copper corrodes at insignificant rates when used in areas with unpolluted air, non-oxidizing acids, and water. However, it happens more rapidly with the presence of road salt, ammonia, sulfur, oxidizing acids

Acidic substances react with the surface of copper, causing it to tarnish and corrode almost instantly. This corrosion is highly soluble, leading to the presence of toxic copper salts in the food. This is why it is not recommended to use copper vessels for foods high in acidity, such as milk, wine, or vinegar.

4 0

2 years ago