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3 years ago

Please help me with chemistry. Thanks

Chemistry

2 answers:

il63 [147K]3 years ago

7 0

Constant:
Test tubes

Independent:
volume of gas

Dependent:

amount of H2O2

olga2289 [7]3 years ago

6 0

Hello there!

A constant stays the same so is the test tube.
An independent variable is changed to test the effects so is the volume of gas.
A dependent variable is being tested and so is the amount of H2O2.

Hope This Helps You!
Good Luck :)

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If the length, width, and height of a box are 10.00 cm, 7.25 cm and 3.00 cm, respectively, what is the volume of the box in unit

Blizzard [7]

Answer:

For a: The volume of the box is 217.5 mL

For b: The volume of the box is 0.2175 L

Explanation:

The box is a type of cuboid.

To calculate the volume of cuboid, we use the equation:

$V=lbh$

where,

V = volume of cuboid

l = length of cuboid = 10.00 cm

b = breadth of cuboid = 7.25 cm

h = height of cuboid = 3.00 cm

Putting values in above equation, we get:

$V=10.00\times 7.25\times 3.00=217.5cm^3$

For a:

To convert the volume of cuboid into milliliters, we use the conversion factor:

$1mL=1cm^3$

So,

$\Rightarrow 217.5cm^3\times (\frac{1mL}{1cm^3})\\\\\Rightarrow 217.5mL$

Hence, the volume of the box is 217.5 mL

For b:

To convert the volume of cuboid into liters, we use the conversion factor:

$1L=1000cm^3$

So,

$\Rightarrow 217.5cm^3\times (\frac{1L}{1000cm^3})\\\\\Rightarrow 0.2175L$

Hence, the volume of the box is 0.2175 L

3 0

3 years ago

Muscles work in _____ so when other muscles contract the other ___

abruzzese [7]

The first word could be: pairs and the second: relax

8 0

3 years ago

Answer the following questions based on the reaction below: NaOH(aq) + KHP(s) --> NaKP(aq)+H2O(I)

Natali [406]

Answer:

a) 1.44g

b) 77.3%

Explanation:

1. Chemical balanced equation (given)

$NaOH(aq)+ KHP(s)\rightarrow NaKP(aq)+H_2O(l)$

2. Mole ratio

$1molNaOH(aq):1molKHP(s)$

This is, 1 mol of NaOH will reacts with 1 mol of KHP.

3. Find the number of moles in 72.14 mL of the base

$Molarity=\text{number of moles of solute}/\text{volume of solution in liters}$

$\text{Volume of solution}=72.14mL=0.07214liters$

$\text{Number of moles of NaOH}=0.0978M\times 0.07214liter=0.007055mol$

4. Find the number of grams of KHP that reacted

The number of moles of KHP that reacted is equal to the number of moles of NaOH, 0.007055 mol

Convert moles to grams:

mass = number moles × molar mass = 0.007055mol × 204.23g/mol

mass = 1.4408 g.

You have to round to 3 significant figures: 1.44 g (because the molarity is given with 3 significant figures).

5. Find the percentage of KHP in the sample

The percentage is how much of the substance is in 100 parts of the sample.

The formula is:

% = (mass of substance / mass of sample) × 100

% = (1.4408g/ 1.864g) × 100 = 77.3%

7 0

3 years ago

How many grams of the excess reactant remain assuming the reaction goes to completion and that you start with 15.5g of na2s and

tangare [24]

The reaction between Na2S and CuSO4 will give us the balanced chemical reaction of,
Na2S + CUSO4 --> Na2SO4 + CuS
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3 years ago

Read 2 more answers

Blank + BaCl2 = BaSO4 + 2NaCl

crimeas [40]

The blank is filled by Na₂SO₄, and the complete equation for the double displacement reaction is:

Na₂SO₄ + BaCl₂ = BaSO₄ + 2 NaCl

<h3>What is a double displacement reaction?</h3>

It is a reaction in which both reactants exchange anions and cations.

Let's consider the following incomplete double displacement reaction.

_____ + BaCl₂ = BaSO₄ + 2 NaCl

If we compare the left and right sides, we can see that the missing ions in the left side are Na⁺ and SO₄²⁻. Thus, the missing compound is Na₂SO₄. The complete equation is:

Na₂SO₄ + BaCl₂ = BaSO₄ + 2 NaCl

Learn more about double displacement here: brainly.com/question/23918356

#SPJ1

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