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3 years ago

Sorah, Sammie,Victor, Vicki, ond Valerie are in math group. Two students are randomly picked to

Chemistry

1 answer:

hodyreva [135]3 years ago

7 0

Answer:

$\frac{2}{5}$

Explanation:

Probability refers to chances of occurrence of any event.

Value of probability is greater than or equal to 0 and less than or equal to 1.

Probability = Number of favorable outcomes ÷ Total number of outcomes

Total number of students in math group = 5

Also, 2 students are randomly picked to be the co-captains.

Probability that students were Sammie and Victor = $\frac{2}{5}$

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Solutions of sulfuric acid and lead(II) acetate react to form solid lead(II) sulfate and a solution of acetic acid. 4.90 g of su

GaryK [48]

Answer:

Mass H2SO4 = 3.42 grams

Mass of lead acetate = 0 grams

Mass PbSO4 = 4.58 grams

Mass of CH3COOH = 1.81 grams

Explanation:

Step 1: Data given

Mass of sulfuric acid = 4.90 grams

Molar mass of sulfuric acid = 98.08 g/mol

Mass of lead acetate = 4.90 grams

Molar mass of lead acetate = 325.29 g/mol

Step 2: The balanced equation

H2SO4 + Pb(C2H3O2)2 → PbSO4 + 2CH3COOH

Step 3: Calculate moles

Moles = mass / molar mass

Moles H2SO4 = 4.90 grams / 98.08 g/mol

Moles H2SO4 = 0.0500 moles

Moles lead acetate = 4.9 grams / 325.29 g/mol

Moles lead acetate = 0.0151 moles

Step 4: Calculate the limiting reactant

For 1 mol H2SO4 we need 1 mol lead acetate to produce 1 mol PbSO4 and 2 moles CH3COOH

The limiting reactant is lead acetate. It will completzly be consumed (0.0151 moles). H2SO4 is in excess. There will react 0.0151 moles. There will remain 0.0500 - 0.0151 = 0.0349 moles

Step 5: Calculate moles of products

For 1 mol H2SO4 we need 1 mol lead acetate to produce 1 mol PbSO4 and 2 moles CH3COOH

For 0.0151 moles lead acetate we'll have 0.0151 moles PbSO4 and 2*0.0151 = 0.0302 moles CH3COOH

Step 6: Calculate mass

Mass = moles * molar mass

Mass H2SO4 = 0.0349 moles * 98.08 g/mol

Mass H2SO4 = 3.42 grams

Mass PbSO4 = 0.0151 moles * 303.26 g/mol

Mass PbSO4 = 4.58 grams

Mass of CH3COOH = 0.0302 moles * 60.05 g/mol

Mass of CH3COOH = 1.81 grams

5 0

4 years ago

The piece of metal is magnetic

Alex_Xolod [135]

Answer:

Explanation:

Magnetic materials are always made of metal, but not all metals are magnetic. Iron is magnetic, so any metal with iron in it will be attracted to a magnet. Steel contains iron, so a steel paperclip will be attracted to a magnet too. Most other metals, for example aluminium, copper and gold, are NOT magnetic.

5 0

3 years ago

A proton is also known as this symbol, _____ ion.

mr Goodwill [35]

Hydrogen ion, strictly, the nucleus of a hydrogen atom separated from its accompanying electron. The hydrogen nucleus is made up of a particle carrying a unit positive electric charge, called a proton. The isolated hydrogen ion, represented by the symbol H+, is therefore customarily used to represent a proton.

4 0

3 years ago

These substances are all ____. H2O2 Li NaCl O2

Bogdan [553]

Answer: pure substances.

Explanation:

The given substances are:

H₂O₂
Li
NaCl
O₂

All what surrounds us, which has mass and occupies spaces, is matter. There are two kind of matter: pure substances and mixtures.

Pure substances have a uniform and constant composition. On the other hand, mixtures are combinations of two or more pure substances in any arbitratry ratio.

Pure substances may be elements or compounds. The elements are the substances conmposed by one only kind of atom. In the list of substances given, Li and O₂ are elements: all the atoms in Li are lithium, and all the atoms in O₂ are oxygen atoms.

Compounds are the chemical combination of two or more different kind of atoms. In the given list H₂O₂ and NaCl are compounds. As you see, H₂O₂ contains atoms of hydrogen and oxygen, chemically bonded, in a fixed ratio (2 atoms of hydrogen by 2 atoms of oxygen). And NaCl has atoms of Na (sodium) and Cl (chlorine), chemicaly bonded, in a fixed ratio (1:1).

There are only 118 known elements and you can find them in any modern periodic table. Therer are virtually infinitely many compounds since many different combinations of the elements can be attained.

Elements and compounds have in common that they are classified as pure substances.

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4 years ago

Glucose is made up of hydrogen, oxygen, and carbon atoms.

MrRa [10]

Answer:

brainly.com/question/11792047

6 0

2 years ago