Questions
± Percent Ionization In addition to the acid-dissociation constant, Ka, another measure of the strength of...

± Percent Ionization

In addition to the acid-dissociation constant, Ka, another measure of the strength of an acid is percent ionization, determined by the following formula:

Percent ionization=[HA] ionized[HA] initial×100%

Percent ionization increases with increasing Ka. Strong acids, for which Ka is very large, ionize completely (100%). For weak acids, the percent ionization changes with concentration. The more diluted the acid is, the greater percent ionization.

A convenient way to keep track of changing concentrations is through what is often called an I.C.E table, where I stands for "Initial Concentration," C stands for "Change," and E stands for "Equilibrium Concentration." To create such a table, write the reaction across the top, creating the columns, and write the rows I.C.E on the left-hand side.

Initial (M)Change (M)Equilibrium (M)A+ B→AB

A certain weak acid, HA, has a Ka value of 8.5×10−7.

Part A

Calculate the percent ionization of HA in a 0.10 M solution.

Express your answer to two significant figures and include the appropriate units.

SubmitHintsMy AnswersGive UpReview Part

Part B

Calculate the percent ionization of HA in a 0.010 M solution.

Express your answer to two significant figures, and include the appropriate units.

SubmitHintsMy AnswersGive UpReview Part

Provi

In: Chemistry

In human cells, the activity of ____________ is required to set the transition from G1 to S phase in motion.

 

QUESTION 21

In human cells, the activity of ____________ is required to set the transition from G1 to S phase in motion.

   

only a cyclin

   

only a cyclin-dependent kinase (CDK)

   

a CDK complexed to a cyclin

   

an RNA-induced silencing complex

   

the telomerase enzyme

QUESTION 22

Transgenic crop plants engineered by recombiant DNA technology can express genes derived from

   

Another crop variety of the same species

   

Another plant species of the same genus

   

Another eukaryotic organism

   

Another cellular organism, but not viruses

   

Any oprganism, including viruses

QUESTION 23

Which of the following occurs in both meiosis and mitosis?

   

Pairing and synapsis of homologous chromosomes.

   

Formation of synaptonemal complex between homologous pairs of chromosomes.

   

Non-sister chromatids exchange large fragments of DNA between one-another.

   

Chromosomes condense, nuclear membrane dissolves.

   

Both sister chromatids of a chromosome are pulled to the same pole of the cell in anaphase.

  

QUESTION 24

What is the name of the protein structure on the eukaryotic chromosome that makes physical contact with the spindle fibers during metaphase of mitosis?

   

Origin of transfer

   

Kinetochores

   

Origins of replications

   

Telomere

   

Separase

QUESTION 25

_______________bacterial strains are able to grow in minimal medium which provides only inorganic nutrients and a carbon source.

   

Obligate biotrophic

   

Prototrophic

   

Necrotrophic

   

Heterotrophic

   

Auxotrophic

QUESTION 26

Retroviruses can cause cancer by

   

Bringing the cell cycle to an abrupt stop.

   

Triggering the expression of tumor suppressor genes.

   

Erroneously activating the transcription of the host cellâ s proto-oncogenes from a strong viral promoter.

   

induction of programmed cell death

   

by injecting base analogues into host cells

QUESTION 27

Which procedure requires the removal of a single cell from a morula-stage human embryo?

   

Pre-implantation genetic diagnosis

   

Reproductive cloning

   

Therapeutic cloning

   

Cloning a PCR fragment in plasmid vector

   

The genetic tansformation of a plant

QUESTION 28

The construction of a cDNA library involves the following steps: (A) purification of mRNA from cells; (B) insertion of the double-stranded cDNA into a vector; (C) synthesis of the second cDNA strand; (D) annealing of oligo(dT) primers to polyA tails and reverse transcription of the first cDNA strand. The correct order in which these steps are performed is:

   

A, B, C, D.

   

A, D, B, C.

   

D, C, A, B.

   

B, A, C, D.

   

A, D, C, B

QUESTION 29

The cultivated coffee (Coffea arabica) is a fertile allotetraploid species with a 2n chromosome number of 44. How many chromosomes are in the gametes of Coffea arabica?

   

Cannot be determined, because an allotetraploid species produces unbalanced gametes with varying number of chromosomes.

   

11

   

22

   

33

   

44

In: Biology

San opening a branch in other city in the country, the following is unadjusted trial balance...

San opening a branch in other city in the country, the following is unadjusted trial balance for san and its branch for the year ended 31/12/2019

Trail balance 31/12/2019:

                                                   San                      branch        

Cash

22000

10175

account /rec.

12000

7550

Investment in Branch

60000

Inventories1/1/2019

23000

11000

Allowance for valuation

(1000)

Prepaid rent

8000

8450

Equipment

177000

32450

Ordinary shares

(200,000)

Retained earning1/1/2019

(34,000)

Dividend

15000

Account payable

(35000)

(2725)

Home office

(51000)

Purchases

190,000

Shipment from home office

104500

Shipment to branch

(110,000)

Sales

(169000)

(144700)

Operating expenses

42000

24300

total

0000

0000

The following information are available for you not considered in the trial balance:

1- the branch sent 1700$ cash for the home office in 31/12/2019.

2- the home office replenished the branch petty cash in 31/12/2019 by 1800$ in transit.

3- the home office shipped the goods for the branch at markup %10.

4- goods in transit for branch at cost was $5000.

5- ending inventory in san company was $30,000 and 9,900 in branch

Required:

1-Prepare the entries required to reconcile the home office and investment accounts?

2- prepare adjusted trial balance for san and its branch?

3- prepare a working paper for combined financial statement for san company in 31/12/2019?

4- prepare closing entries in branch and san books?

In: Accounting

San opening a branch in other city in the country, the following is unadjusted trial balance...

San opening a branch in other city in the country, the following is unadjusted trial balance for san and its branch for the year ended 31/12/2019

Trail balance 31/12/2019:

                                                   San                      branch        

Cash

22000

10175

account /rec.

12000

7550

Investment in Branch

60000

Inventories1/1/2019

23000

11000

Allowance for valuation

(1000)

Prepaid rent

8000

8450

Equipment

177000

32450

Ordinary shares

(200,000)

Retained earning1/1/2019

(34,000)

Dividend

15000

Account payable

(35000)

(2725)

Home office

(51000)

Purchases

190,000

Shipment from home office

104500

Shipment to branch

(110,000)

Sales

(169000)

(144700)

Operating expenses

42000

24300

total

0000

0000

The following information are available for you not considered in the trial balance:

1- the branch sent 1700$ cash for the home office in 31/12/2019.

2- the home office replenished the branch petty cash in 31/12/2019 by 1800$ in transit.

3- the home office shipped the goods for the branch at markup %10.

4- goods in transit for branch at cost was $5000.

5- ending inventory in san company was $30,000 and 9,900 in branch

Required:

1-Prepare the entries required to reconcile the home office and investment accounts?

2- prepare adjusted trial balance for san and its branch?

3- prepare a working paper for combined financial statement for san company in 31/12/2019?

4- prepare closing entries in branch and san books?

In: Accounting

Richard, Barry and Andrew decided to enter into a partnership agreement as from 1st July 2018,...

Richard, Barry and Andrew decided to enter into a partnership agreement as from 1st July 2018, some of the provisions of which were as follows.

1.       Richard to contribute $24000 cash, inventory the fair value of which was $51000, plant and machinery $94320, accounts receivable totalling $15240

2.       Barry to contribute $45000 cash and act as manager for the business at an annual salary of $38400 to be allocated to him at the end of each year.

3.       Andrew to contribute $19800 cash, land $144000, premises $288000, furniture and fittings $48600, and motor vehicles $37800. A mortgage of $216000 secured over the premises was outstanding and the partnership agreed to assume the mortgage.

4.       Profits or losses of the firm to be divided between or borne by Richard, barry and Andrew in the proportion of 2:1:3 respectively.

5.       Interest to be allowed at 8% p.a. on the capital contribution by the partners. Interest at 10% p.a. to be charged on partners’ drawings.

6.       During the year ended 30 June 2019, the income of the partnership totaled $144960, and the expenses (excluding interest on capital and drawings and Barry’s salary) amounted to $51600.

7.       Richard withdrew $14400 on 1 October 2018 and $9600 on 1 January 2019; Barrie withdrew $4800 only on 1 April 2019; Andrew withdrew $12000 on 30 June 2019.

Required

A) Prepare general journal entries necessary to open the records of the partnership.

B) Prepare the balance sheet of the partnership immediately after formation.

C) Prepare a Profit Distribution account for the year ended 30 June 2019.

In: Accounting

Richard, Barry and Andrew decided to enter into a partnership agreement as from 1st July 2018,...

Richard, Barry and Andrew decided to enter into a partnership agreement as from 1st July 2018, some of the provisions of which were as follows.

1.       Richard to contribute $24000 cash, inventory the fair value of which was $51000, plant and machinery $94320, accounts receivable totalling $15240

2.       Barry to contribute $45000 cash and act as manager for the business at an annual salary of $38400 to be allocated to him at the end of each year.

3.       Andrew to contribute $19800 cash, land $144000, premises $288000, furniture and fittings $48600, and motor vehicles $37800. A mortgage of $216000 secured over the premises was outstanding and the partnership agreed to assume the mortgage.

4.       Profits or losses of the firm to be divided between or borne by Richard, barry and Andrew in the proportion of 2:1:3 respectively.

5.       Interest to be allowed at 8% p.a. on the capital contribution by the partners. Interest at 10% p.a. to be charged on partners’ drawings.

6.       During the year ended 30 June 2019, the income of the partnership totaled $144960, and the expenses (excluding interest on capital and drawings and Barry’s salary) amounted to $51600.

7.       Richard withdrew $14400 on 1 October 2018 and $9600 on 1 January 2019; Barrie withdrew $4800 only on 1 April 2019; Andrew withdrew $12000 on 30 June 2019.

Required

A) Prepare general journal entries necessary to open the records of the partnership.

B) Prepare the balance sheet of the partnership immediately after formation.

C) Prepare a Profit Distribution account for the year ended 30 June 2019.

PLEASE DO NOT COPY OTHERS ANSWERS

In: Accounting

In a survey of 848 human resource professionals concerning challenges they faced in the​ workplace, 319...

In a survey of 848 human resource professionals concerning challenges they faced in the​ workplace, 319

said that employee​ retention/turnover was an important challenge and 195 said that employee satisfaction was an important challenge. Complete parts​ (a) through​ (c) below.

a. Construct a​ 95% confidence interval estimate of the population proportion of human resource professionals who believe that employee​ retention/turnover was an important challenge.

The​ 95% confidence interval estimate for the population proportion is

_< π<_

​(Round to four decimal places as​ needed.)

b. Construct a​ 95% confidence interval estimate of the population proportion of human resource professionals who believe that employee satisfaction was an important challenge.

The​ 95% confidence interval estimate for the population proportion is

_≤π≤_

​(Round to four decimal places as​ needed.)

c. How would a human resource professional use the results of​ (a) and​ (b)?

The proportion of survey respondents that said employee​ retention/turnover was an important challenge was

▼ Options

equal to

greater than

less than

the proportion of survey respondents that said employee satisfaction was an important​ challenge, and the two confidence intervals

▼Options

overlap,

do not overlap,

so a human resource professional

▼Options

would want to prioritize turnover/retention

could reasonably pioritize either issue

would want to prioritize satisfaction

Would want to prioritize satisfaction

In: Statistics and Probability

1. An occurrence of a gene made larger by trinucleotide repeats is: Allelic expansion Nucleotide expansion...

1. An occurrence of a gene made larger by trinucleotide repeats is:

Allelic expansion

Nucleotide expansion

Translocation mutation

Transformation

2. a chemical that can damage and/or change DNA is called a/an:

Allele

Endonuclease

Vector

Mutagen

3. An occurrence when a section of a chromosome relocates itself to an entirely different (non-homologous) chromosome is called a/an:

Inversion mutation

Translocation mutation

Transformation mutation

Duplication mutation

4. The tandem repeat in the sequence GGGAAGGGAAGGGAAGGGAAGGGAAG is:

GGA

GGGAA

GGAAG

GGAAGGG

A disease characterized by abnormally shaped hemoglobin is called:

Cystic Fibrosis

Sickle Cell Anemia

Marfan Syndrome

Leukemia

5. A point mutation that causes a substitution of a stop codon with an amino acid and leads to the formation of a longer protein is a:

Nonsense mutation

Missense mutation

Sense mutation

Frameshift mutation

6. Addition or deletion of nucleotides in a DNA sequence is known as a:

Nonsense mutation

Missense mutation

Sense mutation

Frameshift mutation

7. The least severe type of chromosomal mutation is:

Point

Frameshift

Inversion

Translocation

8. Chemicals inserting themselves into DNA can cause a:

Missense mutation

Nonsense mutation

Sense mutation

Frameshift mutation

9. A genetic condition caused by allelic expansion is:

Familial hypercholesterolemia

Fragile X syndrome

Alkaptonuria

Galactosemia

10. Which of the following is most likely the original DNA strand if the mutated DNA strand is ATAGUUGATGUA ?

ATAGAAGATGAA

ATAGCCGATGCA

ATAGGGGATGGA

ATAGTTGATGTA

11. An unbalanced chromosomal mutation would include a/an:

duplication (insertion)

inversion

translocation

denaturation

12. Many translocation mutations are found to be involved with:

cancers

sickle cell anemia

Huntington disease

cystic fibrosis

13. A common repeat throughout the human genome that is approximately 300 bases in length is called a/an:

EcoRI repeat

Hind repeat

Exo repeat

Alu repeat

14. A balanced chromosomal mutation includes:

imprintation

denaturation

inversion

deletion

In: Biology

Consider the following:         Enzyme immunoassay (EIA) tests are used to screen blood specimens for the...

Consider the following:  

      Enzyme immunoassay (EIA) tests are used to screen blood specimens for the presence of antibodies to HIV,  

      the virus that causes AIDS. Antibodies indicate the presence of the virus. The test is quite accurate but is

      not always correct. Suppose that 1% of a large population carries antibodies to HIV in their blood. Of

      those that carry the HIV antibodies in their blood, 99.85% will have a positive test result and 0.15% will

      have a false-negative test result. Of those that do not carry the HIV antibodies in their blood, 99.4% will

      have a negative test result and 0.60% will have a false-positive test result.

  1. Draw a tree diagram for selecting a person from this population and testing his or her blood.

b) Construct a probability table that shows the probabilities for individuals in this population with    

respect to the presence of antibodies and test results.

In: Statistics and Probability

When an organic sulfate ester is hydrolyzed by a sulfatase enzyme, a hydrogen ion is produced;...

When an organic sulfate ester is hydrolyzed by a sulfatase enzyme, a hydrogen ion is produced;

R-O-SO3- + H2O ----> ROH + SO4-2 + H+

The above reaction was carried out in a 1.0 mL of a .02 M Tris buffer, pH 8.10, containing 0.01 M ester. At the end of 10 minutes, the pH of the reaction mizture decreases to 7.95. How many micromoles of ester were hydrolyzed during the 10 minute reaction period? pKa of Tris = 8.10.

In: Chemistry