Which element listed has the least metallic character? A. Na B. Mg C. Al D. Si

Which is a balanced chemical equation? A. C7H16 + 5O2 6CO2 + 4H2O B. C7H16 + 11O2 7CO2 + 8H2O C. C7H16 + 14O2 7CO2 +5H2O D. C7H1

nadya68 [22]

Answer:

$\boxed{\text{B.}}$

Explanation:

B.

$\rm C$_7$H_{16}$ + 11O$_2$ $\longrightarrow \,$ 7CO$_2$ + 8H$_2$O$

BALANCED. 7C, 16H, and 22O on each side of equation.

A.

$\rm C$_7$H$_{16}$ + 5O$_2$ $\longrightarrow \,\rm 6CO$_2$ + 4H$_2$O$

NOT BALANCED. 7C on left and 6C on right.

C.

$\rm C$_7$H$_{16}$ + 14O$_2$ $\longrightarrow \,$ 7CO$_2$ + 5H$_2$O$

NOT BALANCED. 16H on left and 10H on right.

D.

$\rm C$_7$H$_{16}$ + 22O$_2$ $\longrightarrow \, $ 14CO$_2$ + 16H$_2$O$

NOT BALANCED. 7C on left and 14C on right.

3 0

4 years ago

what is the molarity of a solution prepared by dissolving 1.25g of HCL gas into enough water to make 30cm cube of solution?

Tpy6a [65]

Molars are cavities in your teeth the dentists will scrape them out and fill them in for you at your earliest convinence need help with anything else while im here i can assist you!

4 0

3 years ago

150 ml of 0.1 m naoh is added to 200 ml of 0.1 m formic acid, and water is added to give a final volume of 1 l. what is the ph o

N76 [4]

Number of moles of NaOH = V(NaOH) * M(NaOH)= 0.150 L * 0.1 moles/L = 0.015 moles

Number of moles of formic acid, HCOOH = V(HCOOH) * M(HCOOH) = 0.200 L * 0.1 moles/L = 0.020 moles

Here, the limiting reagent is NaOH

The reaction is represented as:

HCOOH + NaOH ↔HCOONa + H2O

Moles of HCOONa formed = Moles of the limiting reagent, NaOH = 0.015 moles

Moles of HCOOH remaining = 0.020-0.015 = 0.005 moles

Total final volume is given as 1 L

Therefore: [HCOOH] = 0.005 moles/1 L = 0.005 M

[HCOONa] = 0.015/1 = 0.015 M

pKa of HCOOH = 3.74

As per Henderson-Hasselbalch equation

pH = pka + log[HCOONa]/[HCOOH] = 3.74+log[0.015/0.005] = 4.22

Therefore, pH of the final solution = 4.22

3 0

4 years ago

Binary ionic and binary molecular compounds have what two things that are similar in their composition

Sonbull [250]

Best Answer: Ionic binary compounds -- contain a metal cation and an anion made of a nonmetal or a polyatomic anion. Consider calcium phosphate:
Ca = 2+ (Group IIA)
PO4 = 3- (phosphate)
The lowest common multiple of 2+ and 3- is 6. You must have 3 Ca2+ to make +6; you must have 2 PO43- to make -6. The sum of the positive and negative charges must be equal in a compound because they are electrically neutral.
Ca3(PO4)2 -- calcium phosphate

Binary molecular compounds -- contain two or more nonmetals bonded covalently. There are no ions present because the atoms share electrons. Prefixes are used to indicate the number of atoms of each kind present. Examples are:
SO2 -- sulfur dioxide
N2O4 -- dinitrogen tetraoxide
PCl3 -- phosphorous trichloride
CO -- carbon monoxide

The general formula for an acid is HX, where X is an anion. Binary acids contain H and a nonmetal and are named with the prefix "hydro" and the suffix "ic". Examples are:
HCl -- hydrochloric acid
H2S -- hydrosulfuric acid
HF -- hydrofluoric acid
Ternary acids contain H and a polyatomic anion. Examples are:
H2SO4 -- sulfuric acid
HNO3 -- nitric acid
HNO2 -- nitrous acid
HClO3 -- chloric acid
HClO2 -- chlorous acid
HClO -- hypochlorous acid
The names of the anions are changed as follows:
-ate anions form -ic acids
-ite anions form -ous acids
per...ate anions form per...ic acids
hypo...ite anions form hypo...ous acids.

3 0

3 years ago

Which is the Lewis structure for H3PO4?

Fed [463]

Answer:

The correct structure of phosphoric acid is A.

Explanation

P should form five covalent bonds. In this strcuture P form three single bond with 3-hydroxyl groups while one single bondformed with oxygen. As oxygen will form two bonds , it carry negative charge, while P should form five bond but here it is forming 4 bonds due to this P has positive charge but overall structure contain neutral charge due to cancellation of positive and negative charges. Beside this, there are 3 H, Four O and One P according to formula H3PO4.

5 0

4 years ago