7. A bicycle rider is traveling up a hill. When the rider reaches the top of the hill, she

2.(04.01 LC)

Mila [183]

Answer:

2KClO3 —> 2KCl + 3O2

The coefficients are 2, 2, 3

Explanation:

From the question given above, we obtained the following equation:

KClO3 —> 2KCl + 3O2

The above equation can be balance as follow:

There are 2 atoms of K on the right side and 1 atom on the left side. It can be balance by putting 2 in front of KClO3 as shown below:

2KClO3 —> 2KCl + 3O2

Now, the equation is balanced.

Thus, the coefficients are 2, 2, 3

8 0

2 years ago

An arctic weather balloon is filled with 27.8 L of helium gas inside a prep shed. The temperature inside the shed is . The ballo

Liula [17]

The question is incomplete, here is a complete question.

An arctic weather balloon is filled with 27.8 L of helium gas inside a prep shed. The temperature inside the shed is 13 ⁰C. The balloon is then taken outside, where the temperature is -9 ⁰C. Calculate the new volume of the balloon. You may assume the pressure on the balloon stays constant at exactly 1 atm. Be sure your answer has the correct number of significant digits.

Answer : The new volume of the balloon is 25.7 L

Explanation :

Charles's Law : It is defined as the volume of the gas is directly proportional to the temperature of the gas at constant pressure and number of moles.

$V\propto T$

or,

$\frac{V_1}{T_1}=\frac{V_2}{T_2}$

where,

$V_1$ = initial volume of gas = 27.8 L

$V_2$ = final volume of gas = ?

$T_1$ = initial temperature of gas = $13^oC=273+13=286K$

$T_2$ = final temperature of gas = $-9^oC=273+(-9)=264K$

Now put all the given values in the above equation, we get:

$\frac{27.8L}{286K}=\frac{V_2}{264K}$

$V_2=25.7L$

Therefore, the new volume of the balloon is 25.7 L

3 0

2 years ago

Which of the following is the correctly balanced chemical equation for the reaction of Ca(OH)2 and HNO3?

sattari [20]

Explanation:

The reaction between calcium hydroxide and nitric acid is as follows.

$Ca(OH)_{2} + HNO_{3} \rightarrow Ca(NO_{3})_{2} + H_{2}O$

Number of reactant atoms are as follows.

Ca = 1
O = 4
H = 3
N = 1

Number of product atoms are as follows.

Ca = 1
O = 4
H = 2
N = 3

To balance the given chemical equation, multiply $HNO_{3}$ by 2 on reactant side and multiply $H_{2}O$ by 2 on the product side.

Therefore, the balanced chemical equation will be as follows.

$Ca(OH)_{2} + 2HNO_{3} \rightarrow Ca(NO_{3})_{2} + 2H_{2}O$

4 0

3 years ago

Arrange the following substance into acid,base and neutral. sodium chloride, tomato juice, vinegar,sea water,bicorbonate of sodi

pantera1 [17]

Answer:

sodium chloride: neutral.

tomato juice: acid.

vinegar: acid.

sea water: base.

bicarbonate of sodium: base.

Explanation:

Hello there!

In this case, in agreement to the definition of the pH, as the measure of the acidity and basicity of a substance; it is important to recall that pH's below 7 stand for acidic substances and pH's above 7 stand for basic substances, whereas a pH of 7 defines a neutral one. In such a way, given the pH's of the given substances, 7, 4.05 to 4.65, around 2.5, about 8.1 and about 8.3 respectively for sodium chloride, tomato juice, vinegar, sea water, bicarbonate of sodium, it is possible to assert:

sodium chloride: neutral.

tomato juice: acid.

vinegar: acid.

sea water: base.

bicarbonate of sodium: base.

Best regards!

3 0

3 years ago

An unknown substance is obtained by police. The forensics laboratory has

timurjin [86]

Answer:

70.0 %

Explanation:

Step 1: Given data

Mass of nitrogen (mN): 74.66 g

Mass of the compound (mNxOy): 250 g

Step 2: Calculate the mass of oxygen (mO) in the compound

The mass of the compound is equal to the sum of the masses of the elements that form it.

mNxOy = mN + mO

mO = mNxOy - mN

mO = 250 g - 74.66 g = 175 g

Step 3: Determine the percent composition of oxygen in the sample

We will use the following expression.

%O = mO / mNxOy × 100%

%O = 175 g / 250 g × 100% = 70.0 %

5 0

2 years ago