Given the unbalanced equation: Al + O2 → Al2O3

An experiment was conducted in order to determine the enthalpy change that occurs when 1.0 mole of ice at 0 degrees Celsius melt

Mashutka [201]

Answer: 1

Explanation:

6 0

3 years ago

Calculate the ph of a 0.005 m solution of potassium oxide k2o

Alecsey [184]

First, we have to see how K2O behaves when it is dissolved in water:

K2O + H20 = 2 KOH

According to reaction K2O has base properties, so it forms a hydroxide in water.
For the reaction next relation follows:

c(KOH) : c(K2O) = 1 : 2

So,

c(KOH)= 2 x c(K2O)= 2 x 0.005 = 0.01 M = c(OH⁻)

Now we can calculate pH:

pOH= -log c(OH⁻) = -log 0.01 = 2

pH= 14-2 = 12

3 0

3 years ago

A marine biologist is preparing a deep-sea submersible for a dive. The sub stores breathing air under high pressure in a spheric

Luba_88 [7]

Complete Question

A marine biologist is preparing a deep-sea submersible for a dive. The sub stores breathing air under high pressure in a spherical air tank that measures 74.0 wide. The biologist estimates she will need 2600 L of air for the dive. Calculate the pressure to which this volume of air must be compressed in order to fit into the air tank. Write your answer in atmospheres. Round your answer to significant digits.

Answer:

The pressure required is $P_2= 12.2 \ atm$

Explanation:

Generally the volume of a sphere is mathematically denoted as

$V_s = \frac{4}{3} * \pi r^3$

Substituting $r = \frac{d}{2} = \frac{74}{2} = 37cm$

$V_s = \frac{4}{3} * 3.42 * (37)^2$

$V_s = 2.121746 *10^5 cm^3$

Converting to Liters

$V_s = \frac{2.121746 *10^5}{1000}$

$V_s= 212.1746L$

Assume that the pressure at which the air is given to the diver is 1 atm when the air was occupying a volume of 2600L

So

From Charles law

$P_1V_1 = P_2 V_s$

Substituting $V_1 =2600 L$ , $P_1 = 1 atm$ , $V_s =212.1746L$ , and making $P_2$ the subject we have

$P_2 = \frac{P_1 * V_1}{V_s}$

$= \frac{1 * 2600}{212.1746}$

$P_2= 12.2 atm$

6 0

4 years ago

Helpppppp please am not good at this

hram777 [196]

The Leaves it's B because to maintain photosynthesis it must be reached through the Leaved

5 0

3 years ago

Read 2 more answers

Write the beta decay equation for the following isotope: 15/6 C?

vesna_86 [32]

Answer:

$\rm _{6}^{15}\text{C} \longrightarrow \, _{-1}^{0}\text{e} + \, _{7}^{15}\text{N}$

Explanation:

The unbalanced nuclear equation is

$\rm _{6}^{15}\text{C} \longrightarrow \, _{-1}^{0}\text{e} + \, ?$

Let's write the question mark as a nuclear symbol.

$\rm _{6}^{15}\text{C} \longrightarrow \, _{-1}^{0}\text{e} + \, _{Z}^{A}\text{X}$

The main point to remember in balancing nuclear equations is that the sums of the superscripts and the subscripts must be the same on each side of the equation.

Then

15 = 0 + A, so A = 15 - 0 = 15, and

6 = -1 + Z, so Z = 6 + 1 = 7

Then, your nuclear equation becomes

$\rm _{6}^{15}\text{C} \longrightarrow \, _{-1}^{0}\text{e} + \, _{7}^{15}\text{X}$

Element 7 is nitrogen, so the balanced nuclear equation is

$\rm _{6}^{15}\text{C} \longrightarrow \, _{-1}^{0}\text{e} + \, _{7}^{15}\text{N}$

8 0

4 years ago