What is the part of the experiment that is measured? * 2 points control group constant independent variable dependent variable?

Which of the following reactions is balanced?

77julia77 [94]

Answer:

B. CaCl₂ + H₂CO₃ → CaCO₃ + 2HC

Explanation:

A balanced reaction has the same number of atoms in the both sides of the reaction. In the options:

A. CaCl₂ + H₂CO₃ → 2CaCO₃ + HCI

In this reaction there is 1 Ca in reactants and 2 in products -The reaction is unbalanced-

There is 1 Ca is both sides, 2Cl, 2H, 1C and 3 Oxygens -The reaction is balanced

C. CaCl₂ + 2H₂CO₃ → CaCO₃ + HCI

There is 1 Ca in both sides but 2Cl in reactants and 1 in Cl -The reaction is unbalanced-

D. 2CaCl₂ + H₂CO₃ →CaCO₃ + HCI

There are 2 Ca in reactants and 1 in Ca -The reaction is unbalanced-

3 0

3 years ago

Which state of matter consists of particles that can be partially compressed? Gas Liquid Plasma Solid

son4ous [18]

Answer: Option (b) is the correct answer.

Explanation:

In liquid state, particles do have kinetic energy that helps in partially overcoming the intermolecular forces between the molecules. But still the particles are close together and they are able to slide past each other.

So, when we apply pressure on a liquid then its molecules partially gets compressed.

On the other hand, molecules of a solid are held together by strong intermolecular forces of attraction. Hence, they have definite shape and volume. As a result, solids do not get compressed.

In gases and plasma state of matter, molecules are gar away from each other. So, they are able to get completely compressed when a pressure is applied.

Thus, we can conclude that liquid is the state of matter which consists of particles that can be partially compressed.

8 0

3 years ago

Please Help!!!

STatiana [176]

Answer:

single replacement

Explanation:

Step 1: Data given

single replacement = A reaction in which one element replaces a similar element in a compound. For example, a metal replaces an other metal.

The general form of a single-replacement (also called single-displacement) reaction is:

A+BC→AC+B

Decomposition = a reaction in which a compound breaks down into two or more simpler substances. The general form of a decomposition reaction is:

AB→A+B

Synthesis = A reaction that occurs when one or more compounds combines to form a complex compound:

A + B → AB

Double replacement: a reaction in which the positive and negative ions of two ionic compounds exchange places to form two new compounds.

The general form of a double-replacement reaction is:

AB+CD→AD+BC

Combustion reaction = a reaction in which a substance reacts with oxygen gas, releasing energy in the form of light and heat. Combustion reactions must involve O2 as one reactant.

The reaction Zn + 2HCl → ZnCl2 + H2

⇒ Does not involve O2 = NOT a combustion reaction

⇒ The compounds do not form a complex compound = NOT a synthesis

⇒ A compound does not break down into smaller substances = NOT a decomposition

⇒ There is a replacement between Zn and H. This is a single replacement, not a double replacement reaction.

6 0

3 years ago

Please help I'm not good at science

Citrus2011 [14]

Answer:

i'm not able to see images but if you type it all i can answer:)

Explanation:

8 0

3 years ago

Burning a compound of calcium, carbon, and nitrogen in oxygen in a combustion train generates calcium oxide , carbon dioxide , n

mylen [45]

The question is incomplete, here is the complete question:

Burning a compound of calcium, carbon, and nitrogen in oxygen in a combustion train generates calcium oxide (CaO), carbon dioxide $(CO_2)$ , nitrogen dioxide $(NO_2)$ , and no other substances. A small sample gives 2.389 g CaO, 1.876 g $CO_2$ , and 3.921 g $NO_2$ Determine the empirical formula of the compound.

Answer: The empirical formula for the given compound is $CaCN_2$

Explanation:

The chemical equation for the combustion of compound having calcium, carbon and nitrogen follows:

$Ca_xC_yN_z+O_2\rightarrow CaO+CO_2+NO_2$

where, 'x', 'y' and 'z' are the subscripts of calcium, carbon and nitrogen respectively.

We are given:

Mass of CaO = 2.389 g

Mass of $CO_2=1.876g$

Mass of $NO_2=3.921g$

We know that:

Molar mass of calcium oxide = 56 g/mol

Molar mass of carbon dioxide = 44 g/mol

Molar mass of nitrogen dioxide = 46 g/mol

For calculating the mass of carbon:

In 44g of carbon dioxide, 12 g of carbon is contained.

So, in 1.876 g of carbon dioxide, $\frac{12}{44}\times 1.876=0.5116g$ of carbon will be contained.

For calculating the mass of nitrogen:

In 46 g of nitrogen dioxide, 14 g of nitrogen is contained.

So, in 3.921 g of nitrogen dioxide, $\frac{14}{46}\times 3.921=1.193g$ of nitrogen will be contained.

For calculating the mass of calcium:

In 56 g of calcium oxide, 40 g of calcium is contained.

So, in 2.389 g of calcium oxide, $\frac{40}{56}\times 2.389=1.706g$ of calcium will be contained.

To formulate the empirical formula, we need to follow some steps:

Step 1: Converting the given masses into moles.

Moles of Calcium = $\frac{\text{Given mass of Calcium}}{\text{Molar mass of Calcium}}=\frac{1.706g}{40g/mole}=0.0426moles$

Moles of Carbon = $\frac{\text{Given mass of Carbon}}{\text{Molar mass of Carbon}}=\frac{0.5116g}{12g/mole}=0.0426moles$

Moles of Nitrogen = $\frac{\text{Given mass of Nitrogen}}{\text{Molar mass of Nitrogen}}=\frac{1.193g}{14g/mole}=0.0852moles$

Step 2: Calculating the mole ratio of the given elements.

For the mole ratio, we divide each value of the moles by the smallest number of moles calculated which is 0.0426 moles.

For Calcium = $\frac{0.0426}{0.0426}=1$

For Carbon = $\frac{0.0426}{0.0426}=1$

For Nitrogen = $\frac{0.0852}{0.0426}=2$

Step 3: Taking the mole ratio as their subscripts.

The ratio of Ca : C : N = 1 : 1 : 2

Hence, the empirical formula for the given compound is $CaCN_2$

3 0

3 years ago