All categories

3 years ago

.Earth’s _____________________ is an imaginary line on which it rotate

Chemistry

2 answers:

Sergio039 [100]3 years ago

4 0

Answer:

axis

Explanation:

mooo

boyakko [2]3 years ago

4 0

It is the equator because our equator shows us the middle of the Earth

You might be interested in

Covalent compounds are generally not very hard. Justify the statement.

Eduardwww [97]

Covalent compounds are generally not very hard because they are formed by two or more nonmetallic atoms.

<h3>COVALENT COMPOUNDS:</h3>

Covalent compounds are compounds whose constituent elements are joined together by covalent bonds.

Covalent bonding occurs when two or more nonmetallic atoms of an element share valence electrons. This means that covalent compounds will not be physically hard since they constitute non-metals.

Examples of covalent compounds are:

H2 - hydrogen
H2O - water
HCl - hydrogen chloride
CH4 - methane

Learn more about covalent compounds at: brainly.com/question/21505413

4 0

3 years ago

3) A certain reaction has the following general form: A + B à AB At a particular temperature the concentration versus time were

seropon [69]

Answer:

a. First order.

b. $k=3.7x10^{-3}s ^{-1}$

c. $t_{1/2}=187.3s$

d. $[A]=0.111M$

Explanation:

Hello.

a. In this case since the slope is in s⁻¹ we can infer that the lineal form of the rate law is:

$ln[A]=-kt+ln[A]_0$

Which is also:

$y=mx+b$

It means that the reaction is first-order as slope equals the negative of the rate constant which also has units of first-oder reaction.

b. Since the slope is −3.7 x 10−3 s−1 the rate constant is:

$k=-m\\\\k=-(-3.7x10^{-3}s ^{-1})\\\\k=3.7x10^{-3}s ^{-1}$

c. For first-order reactions, the half-life is:

$t_{1/2}=\frac{ln(2)}{k}\\ \\t_{1/2}=\frac{ln(2)}{3.7x10^{-3}s^{-1}}\\\\t_{1/2}=187.3s$

d. In this case, since the integrated first-order rate law is:

$[A]=[A]_0exp(-kt)$

The concentration once 220 seconds have passed is:

$[A]=0.250Mexp(-3.7x10^{-3}s^{-1}*220s)\\\\$

$[A]=0.111M$

Regards.

7 0

4 years ago

A student determines the molar mass of acetone

love history [14]

The Formula of Acetone is $C_3H_6O$
To find the Mass Molar of a compound, you add the Atomic weights of it's atoms.
If you check the Periodic table:
Atomic Weight of Carbone C: 12.0107
Atomic Weight of Hydrogen: 1.00794
Atomic Weight of Oxygen: 15.9994

So, you got:
Total Atomic Weight of Carbone in Acetone: 12.0107 * 3 = 36.0321
Total Atomic Weight of Hydrogen in Acetone: 1.00794 * 6 = 6.04764
Total Atomic Weight of Oxygen in Acetone = 15.9994 * 1 = 15.9994

Now, you add this numbers
36.0321 + 6.04764 + 15.9994 = 58.07914

So, the Molar Mass of Acetone is 58.09714 g/mol

Hope this Helps :D

7 0

3 years ago

Rubidium has two naturally occurring isotopes, rubidium -85 ( atomic mass = 84.9118 amu; abundance = 72.15%) and rubidium -87 (a

son4ous [18]

Answer:

The answer to your question is: 85.458 amu

Explanation:

data

Rubidium-85 A = 84.9118 amu abundance = 72.15%

Rubidium - 87 A = 86.9092 amu abundance = 27.85%

Atomic weight = ?

Atomic weight = 84.9118(0.7215) + 86.9092(0.2785)

Atomic weight = 61.2538 + 24.2042

Atomic weight = 85.458 amu

6 0

4 years ago

If 3. 5 grams of ni are reacted with excess oxygen to form nickel oxide unser standard state conditions, what is the entropy cha

Mashutka [201]

Entropy Change is the measure of the randomness of the thermodynamic system. The entropy change for the reaction is -49.3 J/K.

<h3>What is the change in entropy?</h3>

Entropy change is the ratio of the heat transfer of the system to the absolute temperature of the system.

The entropy of nickel = 182.1 J/mol. K

The entropy of oxygen = 205.0 J/mol. K

The entropy of nickel oxide = 37.99 J/mol. K

Entropy change is calculated as:

$\begin{aligned}\Delta \rm S &= 2(37.99)-2(182.1)-205\\\\&= 75.98 - 364.2 - 205\\\\&= -493.22 \end{aligned}$

Therefore, -49.3 J/K is the entropy change.

Learn more about entropy change here:

brainly.com/question/1301642

#SPJ4

8 0

2 years ago