All categories

2 years ago

What do you think is the coldest temperature something can get to? What limits how cold something can get?

Chemistry

1 answer:

damaskus [11]2 years ago

4 0

Answer:

The colder an object it, the slower the atoms are. This is the rule that affects how cold something can get. There is a limit of how cold something can get though. This is called absolute zero. And, actually, we've gotten very close to it. Scientists in Finland have cooled rhodium atoms to a 10th of a billionth of a degree above absolute zero.

You might be interested in

Which member of each pair is the stronger base? part a ethylamine or aniline ethylamine or aniline ethylamine aniline request an

Vladimir79 [104]

Lowery-Bronsted theory is applied here. Acc. to this theory Base accepts protons and Acids donate proton.

Part 1:
Aniline is less basic than ethylamine because the lone pair on nitrogen (which accepts proton) is not localized. It resonates throughout the conjugated system of phenyl ring. Hence due to unavailability of electrons for accepting proton it is less basic compare to ethylamine. In ethyl amine the lone pair of electron is localized and available to abstract proton.

Part 2:
In this case the alkyl groups attached to -NH₂ (in ethylamine) and -O⁻ (in ethoxide are same (i.e. CH₃-CH₂-). Ethoxide is more basic than ethylamine because ethoxide is a conjugate base of ethanol (pKa value of ethanol = 15.9 very weak acid) and the conjugate base of weak acid is always a strong base. Secondly, the oxygen atom more Electronegative than Nitrogen atom can attract more electron cloud from alkyl group as compared to Nitrogen in ethylamine. Hence, oxygen in ethoxide attains greater electron cloud than the nitrogen in ethylamine. Therefore, it is more basic than ethylamine.

5 0

3 years ago

Compare and contrast the terms homologous and analogous.

I am Lyosha [343]

Analogous structures are those structures in different species which perform the same function, have similar appearance and structure but are not evolved together; therefore do not share a common ancestor. Homologous and analogous organs video explains in a simple way.

5 0

3 years ago

14.

crimeas [40]

Answer:

Jeweler B = more accurate

Jeweler A = more precise

Error:

0.008, 0

% error :

0.934% ; 0

Explanation:

Given that:

True mass of nugget = 0.856

Jeweler A: 0.863 g, 0.869 g, 0.859 g

Jeweler B: 0.875 g, 0.834 g, 0.858 g

Official measurement (A) = 0.863 + 0.869 + 0.859 = 2.591 / 3 = 0.864

Official measurement (B) = 0.875 + 0.834 + 0.858 = 2.567 / 3 = 0.8556

Accuracy = closeness of a measurement to the true value

Accuracy = true value - official measurement

Jeweler A's accuracy :

0.856 - 0.864 = - 0.008

Jeweler B's accuracy :

0.856 - 0.856 = 0.00

Therefore, Jeweler B's official measurement is more accurate as it is more close to the true value of the gold nugget.

However, Jeweler A's official measurement is more precise as each Jeweler A's measurement are closer to one another than Jeweler B's measurement which are more spread out.

Error:

Jeweler A's error :

0.864 - 0.856 = 0.008

% error =( error / true value) × 100

% error = (0.008/0.856) × 100% = 0.934%

Jeweler B's error :

0.856 - 0.856 = 0 ( since the official measurement as been rounded to match the decimal representation of the true value)

% error = 0%

3 0

3 years ago

How many grams of Cl are in 525g of CaCl2

Tema [17]

First we determine the moles CaCl2 present:

525g / (110.9g/mole) = 4.73 moles CaCl2 present

Based on stoichiometry, there are 2 moles of Cl for every mole of CaCl2:
(2moles Cl / 1mole CaCl2) x 4.73 moles CaCl2 = 9.47 moles Cl

Get the mass:
9.47moles Cl x 35.45g/mole = 335.64 g Cl

8 0

3 years ago

Mg3N2(s)+6H2O(l)→3Mg(OH)2(s)+2NH3(g) When 36.0 g of H2O react, how many grams of NH3 are produced? When 36.0 g of H2O react, how

Afina-wow [57]

Answer:

11.3 g of $NH_{3}$ are produced from 36.0 g of $H_{2}O$

Explanation:

1. The balanced chemical equation is the following:

$Mg_{3}N_{2}(s)+6H_{2}O(l)=3Mg(OH)_{2}(s)+2NH_{3}(g)$

2. Use the molar mass of the $H_{2}O$ , the molar mass of the $NH_{3}$ and the stoichiometry of the balanced chemical reaction to find how many grams of $NH_{3}$ are produced:

Molar mass $H_{2}O$ = 18 $\frac{g}{mol}$

Molar mass $NH_{3}$ = 17 $\frac{g}{mol}$

$36.0gH_{2}O*\frac{1molH_{2}O}{18gH_{2}O}*\frac{2molesNH_{3}}{6molesH_{2}O}*\frac{17gNH_{3}}{1molNH_{3}}=11.3gNH_{3}$

Therefore 11.3 g of $NH_{3}$ are produced from 36.0 g of $H_{2}O$

3 0

3 years ago