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hoa [83]
3 years ago
10

A substance must be...

Chemistry
1 answer:
grandymaker [24]3 years ago
6 0

Answer:

I think it would be b

Explanation:

pls correct me if im wrong!

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The isomerization of methylisonitrile to acetonitrile (CH3NC(g) ???? CH3CN) is first order in CH3NC. The rate constant for the r
Hoochie [10]

Answer:

The half life is     H_{1/2}= 7333.3sec

Explanation:

   The half life of a first order  reaction is mathematically represented as

                          H_{1/2} = \frac{0.693}{Rate Constant }

 Substituting   9.45 * 10^{-5}s^{-1}  for the rate constant

                         H_{1/2} = \frac{0.693}{9.45*10^{-5}}

                                 H_{1/2}= 7333.3sec

5 0
3 years ago
As an object falls down the earth, its gravitational potential energy will
Travka [436]

Answer:

a. decrease

Explanation:

6 0
3 years ago
An ideal gas contained in a piston-cylinder assembly is compressed isothermally in an internally reversible process.
Tju [1.3M]

Answer:

a) \Delta S

b) entropy of the sistem equal to a), entropy of the universe grater than a).

Explanation:

a) The change of entropy for a reversible process:

\delta S=\frac{\delta Q}{T}

\Delta S=\frac{Q}{T}

The energy balance:

\delta U=[tex]\delta Q- \delta W

If the process is isothermical the U doesn't change:

0=[tex]\delta Q- \delta W

\delta Q= \delta W

Q= W

The work:

W=\int_{V1}^{V2}P*dV

If it is an ideal gas:

P=\frac{n*R*T}{V}

W=\int_{V1}^{V2}\frac{n*R*T}{V}*dV

Solving:

W=n*R*T*ln(V2/V1)

Replacing:

\Delta S=\frac{n*R*T*ln(V2/V1)}{T}

\Delta S=n*R*ln(V2/V1)}

Given that it's a compression: V2<V1 and ln(V2/V1)<0. So:

\Delta S

b) The entropy change of the sistem will be equal to the calculated in a), but the change of entropy of the universe will be 0 in a) (reversible process) and in b) has to be positive given that it is an irreversible process.

7 0
4 years ago
A student needed to make 100.0 mL of 0.20M NaOH solution. How many grams of sodium hydroxide does the student need to weigh out
GuDViN [60]

Answer:

0.08 g

Explanation:

100.0 mL = 0.10 L

Multiply the volume by the molarity to find moles.

0.10 L × 0.20 M = 0.002 mol

Convert moles to grams.

0.002 mol × 40 g/mol = 0.08 g

4 0
4 years ago
Fill in the missing information:
Neko [114]

Answer: 1. Complete Nuclear Symbol : _{22}^{48}{Ti^{4+}}

2. Atomic number : 22

3. Mass number : 48  

4. Charge : 4 +

Explanation:

Atomic number is equal to the number of protons.

Mass number is the sum of number of neelectrons. utrons and number of protons.

Given : no of protons = 22 , thus atomic number = 22

Mass number =  number of neutrons + number of protons

Mass number =  26 + 22 = 48

Also for a neutral atom , the number of protons is equal to the number of electrons. But here electrons are 4 less than protons, which means the atom has lost 4 electrons and thus will have a charge of 4+.

The atomic number is specific to an element, and the element with atomic number 22 is Titanium (Ti). The representation is _{22}^{48}{Ti^{4+}}

3 0
3 years ago
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