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2 years ago

.The 1" row of the periodic table has which two elements?

1 answer:

5 0

On the periodic table, hydrogen and helium are the only two elements in the first row, or period, which reflects that they only have electrons in their first shell. Hydrogen and helium are the only two elements that have electrons exclusively in the 1 s 1s 1s orbital in their neutral, non-charged, state.

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A molecule has a carbon atom that is best described by sp2 hybridization. how many other atoms are connected to this carbon? thr

Aleksandr-060686 [28]

<span>Three atoms can be connected to the carbon atom with sp2 hybridization of a molecule.As sp2 hybridization for three sp2 hybrid orbitals which can only be connected to three other atoms.As an example is the ethene molecule(C2H4) which have 2 Carbon atoms with sp2 hybridization and one Carbon atom is connected with two hydrogen atoms and one carbon atom.</span>

5 0

3 years ago

What is the relationship between particle collisions and reaction rates?

4vir4ik [10]

Answer:

Collision theory states that the rate of a chemical reaction is proportional to the number of collisions between reactant molecules. The more often reactant molecules collide, the more often they react with one another, and the faster the reaction rate.

5 0

3 years ago

A colorless solution is known to contain one of these ions. Which ion is present if adding dilute HCl produces a white precipita

marta [7]

Answer:

The correct answer is option D.

Explanation:

All the cations given belong to the group-1 cation and will give precipitate of their respective chlorides when HCl is added to their aqueous solution.

$Ag^+(aq)+HCl(aq)\rightarrow AgCl(s)+H^+(aq)$

$Cu^{2+}+(aq)+2HCl(aq)\rightarrow CuCl_2(s)+2H^+(aq)$

$Hg_{2}^{2+}+(aq)+2HCl(aq)\rightarrow Hg_2Cl_2(s)+2H^+(aq)$

$Pb^{2+}+(aq)+2HCl(aq)\rightarrow PbCl_2(s)+2H^+(aq)$

All the precipitates are insoluble in cold water but out of all these only lead(II) chloride is soluble in warm water.

4 0

2 years ago

The formula for a compound of Li+ ions and Br- ions is written LiBr. Why can’t it be written Li2Br? Why isn’t it written BrLi?

maksim [4K]

Lithium has charge of +1 and bromide has charge of - 1. So they combine to form the compound lithium bromide which is expressed as LiBr.

<h3><u>Explanation:</u></h3>

Lithium is an alkali metal placed in group 1 or periodic table. It has a valency of 1 which is achieved as lithium loses an electron to achieve a charge of +1.

Bromine is a halogen which is placed in group 17 of periodic table. It has a valency of 1 which is achieved as bromine looses an election to achieve a charge of - 1.

Lithium is the cation and bromide is the anion. So lithium is written in front and bromine following the cation. And as both of their valencies are 1, so they form the compound LiBr.

3 0

3 years ago

Both fructose and glucose have an empirical formula of CH2O and a molecular mass of 180.15948 g/mol. Determine the molecular for

Basile [38]

Answer:

C) C₆H₁₂O₆.

Explanation:

We can determine the molecular formula by calculating the molecular mass of different choices.

Molecular mass = ∑(no. of atoms * atomic mass).

A) CH₂O:

molecular mass = atomic mass of C + 2*atomic mass of H + atomic mass of O = (12.0 g/mol) + (2 * 1.0 g/mol) + (16.0 g/mol) = 30.0 g/mol.

B) C₃H₈O₃:

molecular mass = 3(atomic mass of C) + 8(atomic mass of H) + 3(atomic mass of O) = 3(12.0 g/mol) + 8(1.0 g/mol) + 3(16.0 g/mol) = 92.0 g/mol.

C) C₆H₁₂O₆:

molecular mass = 6(atomic mass of C) + 12(atomic mass of H) + 6(atomic mass of O) = 6(12.0 g/mol) + 12(1.0 g/mol) + 6(16.0 g/mol) = 180.0 g/mol.

D) C₈H₁₆O₈:

molecular mass = 8(atomic mass of C) + 16(atomic mass of H) + 8(atomic mass of O) = 8(12.0 g/mol) + 16(1.0 g/mol) + 8(16.0 g/mol) = 240.0 g/mol.

<em>So, the right choice is: C) C₆H₁₂O₆.</em>

5 0

2 years ago