if theres no coefficient on a element symbol, is the power automatically 1 like it would be if there was no subscript?

For which of the following can a relative age be determined? Select all that apply.

Allushta [10]

Answer: A. fossil

B. rock layer

Explanation:

Relative aging or dating can be define as the technique for determination of the age of the rock and fossil. It is a method of determining the chronological order of the past events by comparing the stratigraphic column of rocks and sediments with each other. This method can only give relative age of one object in comparison with the other but does not give the absolute date.

5 0

2 years ago

C2H4(g) + H2(g) → C2H6(g) ΔH = –137.5 kJ; ΔS = –120.5 J/K Calculate ΔG at 25 °C and determine whether the reaction is spontaneou

Katen [24]

Answer:-ΔG=-101.5KJ

Explanation:We have to calculate ΔG for the reaction so using the formula given in the equation we can calculate the \Delta G for the reaction.

We need to convert the unit ofΔS in terms of KJ/Kelvin as its value is given in terms of J/Kelvin

Also we need to convert the temperature in Kelvin as it is given in degree celsius.

$\Delta H=-137.5\\ \Delta S=-120J/K\\ \Delta S=-0.120KJ/K\\ T=25^{.C}\\ T=273+25=298 K\\ \Delta G=?\\ \Delta G=\Delta H-T\Delta S\\\Delta G=-137.5KJ-(278\times -0.120)\\ \Delta G=-137.5+35.76\\\Delta G=-101.74\\\Delta G=Negative$

After calculating forΔG we found that the value ofΔG is negative and its value is -101.74KJ

For a reaction to be spontaneous the value of \Delta G \ must be negative .

As the ΔG for the given reaction is is negative so the reaction will be spontaneous in nature.

In this reaction since the entropy of reaction is positive and hence when we increase the temperature term then the overall term TΔS would become more positive and hence the value of ΔG would be less negative .

Hence the value of ΔG would become more positive with the increase in temperature.

So we found the value of ΔG to be -101.74KJ

4 0

3 years ago

Read 2 more answers

A sample of quartz is put into a calorimeter (see sketch at right) that contains of water. The quartz sample starts off at and t

pashok25 [27]

Answer:

0.71 J/g°C

Explanation:

Here is the complete question

thermometer A 51.9 g sample of quartz is put into a calorimeter (see sketch at right) that contains 300.0 g of water. The quartz sample starts off at 97.8 °C and the temperature of the water starts off at 17.0 °C. When the temperature of the water stops changing it's 19.3 °C. The pressure remains constant at 1 atm. insulated container water sample Calculate the specific heat capacity of quartz according to this experiment. Be sure your answer is rounded to 2 significant digits. a calorimeter g °C

Solution

Since the temperature of the water increases from 17.0 °C to 19.3 °C, it means that it loses heat. Also, the final temperature of the quartz equals the final temperature of the water 19.3 °C. Since the quartz temperature decreases from 97.8 °C to 19.3 °C it loses heat.

So, heat lost by quartz, Q = heat gained by water, Q'

-Q = Q'

-mc(θ₂ - θ₁) = m'c'(θ₂ - θ₃) where m = mass of quartz = 51.9 g, c = specific heat capacity of quartz, θ₁ = initial temperature of quartz = 97.8 °C, θ₂ = final temperature of quartz = 19.3 °C, m' = mass of water = 300 g, c = specific heat capacity of water = 4.2 J/g °C , θ₃ = initial temperature of water = 17.0 °C, θ₂ = final temperature of water = 19.3 °C

Making c subject of the formula, we have

c = -m'c'(θ₂ - θ₃)/m(θ₂ - θ₁)

Substituting the values of the variables into the equation, we have

c = -300 g × 4.2 J/g °C(19.3 °C - 17.0 °C)/51.9 g(19.3 °C - 97.8 °C)

c = -1260 J/°C(2.3 °C)/51.9 g(-78.5 °C)

c = -2898 J/-4074.15 g°C

c = 0.711 J/g°C

c ≅ 0.71 J/g°C to 2 significant digits

5 0

3 years ago

A teaspoon of powdered caffeine can be as deadly as a teaspoon of ricin. <br><br> True or False

Darina [25.2K]

A teaspoon of caffeine is <em>NOT</em> deadly as teaspoon of ricin

4 0

3 years ago

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Light will interact with objects by making them appear opaque, translucent, or transparent. Please select the best answer from t

lbvjy [14]

Answer:

True (T)

Explanation:

By absorbing or reflecting or letting light pass through, things become opaque, translucent, or transparent.

4 0

3 years ago