LT

This page lists questions and answers that were posted by visitors named LT.

Questions

The following questions were asked by visitors named LT.

1) Find the missing parameter 1.mean 15, 30.15 %, above 50; what is the standard deviation 2.mean 75, 5.05% below 30; what is the standard deviation 3.standard deviation 9, 85.08% below 105: what is the mean 4.standard deviation 16.8, 15.62% above 18.3: w...

It is generally believed that electrical problems affect about 14% of new cars. An automobile mechanic conducts diagnostic tests on 128 new cars on the lot. a. Describe the sampling distribution for sample proportion by naming the model and telling its me...

The International Olympic Committee states that the female participation in the 2000 Summer Olympic Games was 42%, even with new sports such as weight lifting, hammer throw, and modern pentathlon being added to the Games. Broadcasting and clothing compani...

The countries of Europe report that 46% of the labor force is female. The United Nations wonders if the percentage of females in the labor force is the same in the United States. Representatives from the United States Department of Labor plan to check a r...

2. Herpetologists (snake specialists) found that a certain species of reticulated python have an average length of 20.5 feet with a standard deviation of 2.3 feet. The scientists collect a random sample of 30 adult pythons and measure their lengths. In th...

6. In 2000, the United Nations claimed that there was a higher rate of illiteracy in men than in women from the country of Qatar. A humanitarian organization went to Qatar to conduct a random sample. The results revealed that 45 out of 234 men and 42 out...

5. The board of directors for Procter and Gamble is concerned that only 19.5% of the people who use toothpaste buy Crest toothpaste. A marketing director suggests that the company invest in a new marketing campaign which will include advertisements and ne...

A company claims to have invented a hand-held sensor that can detect the presence of explosives inside a closed container. Law enforcement and security agencies are very interested in purchasing several of the devices if they are shown to perform effectiv...

5. There is some indication in medical literature that doctors may have become more aggressive in inducing labor or doing preterm cesarean sections when a woman is carrying twins. Records at a large hospital show that of the 43 sets of twins born in 1990,...

How do I tell if this is a mean or a proportion 1. Insurance companies track life expectancy information to assist in determining the cost of life insurance policies. The insurance company knows that, last year, the life expectancy of its policyholders wa...

How do you tell if the null hypothesis rejects or fails?

What if my p value is below 0.05 does it reject or fail the null hypothesis

Can someone help me start this please: There is some indication in medical literature that doctors may have become more aggressive in inducing labor or doing preterm cesarean sections when a woman is carrying twins. Records at a large hospital show that o...

does anyone know how to do statistics

how do i tell if my graph is linear or nonlinear...

what are outliers and influential points in graphs dealing with data

Solve the system by the addition method -10x^2 + 10y^2-320=0 30x^2 + 6y^2 - 336 = 0

How do i solve for the variable 3x= sqrt5x+1

Solve for the variable m^2 + 2m +3 > = 0

write in interval notation 2x^2 < or = 9x+5

I have to write a short essay on a movie called the seventh seal and I was wondering about a certain part that interested me and that would be where he is playing chess with death can any one give me some help with this... like what does it mean... and ec...

What is the pH of a buffer solution that is 0.15 M propionic acid and 0.20M sodium propionate? How do I start this problem

What is the pH of a buffer solution that is 0.20M methylamine and 0.15 M methylammonium chloride. which do i get the pH of

The pH of a 1.0 x 10^-3 M Ba(OH)2 solution at 25 degrees C is how can 11.3 be the right answer.

a solution saturated in calcium hydroxide(limewater) has a pH of 12.35. What is Ksp for calcium hydroxide? How do i start this problem. please

what is the molar solubility of lead sulfate in 1.0 X 10^-3 M Na2SO4? The Solubility Product Constant PbSO4 Ksp= 1.8 x 10^-8 The Ksp expression is: Na2SO4 = [2Na][SO4^-2] [2Na]=2x [SO4^-2]=x Ksp= 1.8 x 10^-8 = (x)(2x) Ksp= 1.8 x 10^-8 /4x^3 1.8 x 10^-8/4...

If the concentration of a saturated solution of SrCO3 is 0.000040 mol*L^-1, what is the value for the solubility product constant of this salt. How do I start this please

If two salts AX and BX2, have the same Ksp values of 4.0x10^-12 at a given temperature, then A. their molar solubilities in water are the same B. the salts are more soluble in 0.1 M NaX than in water C. the molar solubility of AX in water is less than tha...

The dissociation for a weak base BOH in water found to be 1.25 x 10^-6. What is the concentration of H+ in a 3.2M soluton of BOH.

What is the OH^- concentraton of a solution that is 0.10M in Na2C2O4? I have a couple of these concentration questions asking different things but I don't know how to do them

How do you calculate the pH, pOH, [H3O] and [OH] for a 0.067 M solution of sodium iodate

All of the following species would be expected to be able to function a Lewis bases EXCEPT a. F- b. O2- c. OH+ d. H2O BF3

Which one of the following salts is obtained by the reation of a weak acid with a strong base. MgCl2 NH4F LiClO4 NaCl K2SO3

Equal volumes of 1 M BaCl2 and 1 M NaSO4 are mixed. What effect will the addition of more Na2SO4 solution have on the concentration of Ba^2+ remaining in solution? *No effect *increase the concentration of Ba^2+ ions *Decreases the concentration of Ba^2+...

The ionization constant of an acid, HX is 1 x 10^-5. When a mixture of 0.100 mol HXand 0.100 mol of NaX is diluted to a volume of one liter by addition of wate, the pH of the resulting solution is very nearly a. 7 b. 6 c. 5 d. 4

What is the molar concentration of silver ion in a solution containing 1.3 × 10–4 M CrO42–, saturated with Ag2CrO4? The Solubility Product Constant, Ksp for Ag2CrO4 is 9 × 10–12 (A) 1.3 × 10–16 (B) 7 × 10–16 (C) 9 × 10–12 (D) 2.6 × 10–4 (E) 7 × 10–3

Enough water is added to 0.35 g of benzoic acid to make 1000 mL of solution. What is the pH? Ionization Constant for Benzoic Acid Ka = 6.5 × 10–5 Molar Mass Benzoic Acid 122. g·mol–1 (A) 1.9 (B) 2.6 (C) 3.4 (D) 4.2

Are any of you a teacher... I have an important question that has to a teacher

what is an Incipient Civilizations

Ok this is what i got for the grams part now.... Total mass is 20.14 + 51.64 + 11.34 + 15.06 = 98.18 %H2O = (20.14/98.18)*100 = 20.51% %C2O4 = (51.64/98.18)*100 = 52.60% % Fe 3+ = (11.34/98.15) * 100= 11.55% % K + = (15.06/98.15) * 100 = 15.43 % 20.51 g H...

How do I find the percent composition of H2O: 20.14grams C2O4: 51.64grams Fe 3+: 11.34grams K^+: 15.06 grams and the empirical formula with these numbers

Dr. Bob ok well here is what i have gotten so far: on the problem H2O: 1.118 mol C2O4: .58681 mol Fe 3+: .2025 mol K^+: .3862 mol That is what ive gotten doing 20.14 g(1 mol / 18 g) = 1.118 mol and so on with the rest of them Did i do that wrong

How do i write a good discussion/conclusion for a lab report.

Ok this is what i got for the grams part now.... Total mass is 20.14 + 51.64 + 11.34 + 15.06 = 98.18 %H2O = (20.14/98.18)*100 = 20.51% %C2O4 = (51.64/98.18)*100 = 52.60% % Fe 3+ = (11.34/98.15) * 100= 11.55% % K + = (15.06/98.15) * 100 = 15.43 % 20.51 g H...

Create at least two arguments each pro- and contra the establishment of a Global Culture does any one know about global culture or what it is

Manganese has the oxidation number of +5 in ______ . . (A) [MnF6]3– (C) [MnO4]2– (B) Mn2O7 (D) [Mn(CN)6]–

Free sulfur may act as either an oxidizing agent or a reducing agent. What is the best experimental evidence for this statement? (A) Sulfur forms sulfur dioxide as well as calcium sulfide. (B) Sulfur is a nonmetal. (C) Sulfur forms both organic and inorga...

In the chemical reaction, . Zn(s) + CuSO4(aq) ¨ ZnSO4(aq) + Cu(s), (A) metallic zinc is the reducing agent. (B) metallic zinc in reduced. (C) copper ion is oxidized. (D) sulfate ion is the oxidizing agent.

Which reaction will occur if each substance is in its standard state? (A) Ni2+ will oxidize Sn2+ to give Sn4+ (B) Sn4+ will oxidize Br– to give Br2 (C) Br2 will oxidize Ni(s) to give Ni2+ (D) Ni2+ will oxidize Br2 to give Br–

Which statement is true for the cell as it discharges? Zn | Zn2+(1 .0 M) || Sn2+(1.0 M) | Sn (A) Oxidation occurs at the tin electrode. (B) Electrons will flow from the tin electrode to the zinc electrode. (C) The concentration of Zn2+ will increase. (D)...

Which process represents a general method for the preparation of a metal from its compounds? . (A) neutralization (D) fusion (B) reduction (E) sublimation (C) oxidation

During the electrolysis of an aqueous solution of CuSO4 with inert electrodes (A) the anode loses mass and the cathode gains mass. (B) the mass of the anode remains the same but the cathode gains mass. (C) the mass of the anode decreases but the mass of t...

In every electrolytic and galvanic (voltaic) cell the anode is that electrode (A) at which oxidation occurs. (B) which attracts cations. (C) at which electrons are supplied to the solution. (D) at which reduction occurs.

For there reaction system involving the species in the table below, what conclusion is justified for standard state conditions? Standard Reduction Potentials E0 2Fe3+ + Sn2+ ¡ú 2Fe2+ + Sn4+ +0.62 V Sn2+ + I2 ¡ú Sn4+ + 2I¨C +0.38 V (A) I¨C would react with...

If the ratio of two pulleys, A and B is 4:3, and pulley B has a length of 13.5 inches, how long is pulley A? [a] inches how do i figure this

how do i find the height of a triangle the base is 18 inches, the angled side is 82 inches and it is a right triangle

My teacher is asking me to "Create a two-part answer for the concepts below" what is a two part answer

(square root of x+7)-5 = x Only the x+7 is square rooted how do I find the solution set???

(X+1)/2 = 4 - (X+2)/7

Why is it important to know an accurate VO2 max value when prescribing exercise?

y = sin (x - Pi sign) amplitude: period: phase shift:

The sum of the squares of two numbers is 2. The product of the two numbers is 1. Find the numbers. xy=1 x^2+y^2=2 x^4+1=2x^2 x^4-2x^2+1=0 I don't think you can factor that unless its (x^2+1)(x^2-1) but I don't know where to go from there

x+y=-4 (x-2)^2+(y+7)^2=13 solve by substitution

What does Thomas Paine value highly in the excerpt from his essay “The Crisis”? Freedom Solitude Individuality Spirituality Equality

Choose one archetype that is illustrated by two or more of the stories you have read, and write a brief essay explaining what an archetype is, what archetype you’ve chosen to discuss, and how the archetype is demonstrated in at least two different pieces...

describe the preparation of 100mls of 1,0M from concentrated HCL?

Answers

The following answers were posted by visitors named LT.

Can someone look at my question and my answer on this please

I have the question from my homework that someone can look at and Ive already done all the work so can someone check my answer and help me with it either being rejected or failed

okay I am sorry but that is why I asked this question because I don't understand what all that means. Im gonna guess if the p value is not below 0.05 then it Fails to reject the Null Hypothesis and if it is about 0.05 then it just rejects or fails the nul...

So NH3 is the weak base im guessing

well the only problem im having is finding the pKa

i think i will choose the 4.88 thank you

I follow you so far but how do you calculate OH

So what do i do then to solve for the ksp

So im solving for two expressions... is that it.

ok I got x^2 = 1.8 x 10^-8 = 1.34 x 10^-4 for PbSO4 is this right

Ksp = 4.0E-5 = (x)(3x) is the (3x) squared ??

i subtracted 1E-3 from the 1.8E-8 and it got me a -9.999E-4 then i took the sqrt cause (X)(X) is x^2 and then the calculator told me an error

where i am pulling this is if you pull up google and type in molar solubility the first website shows you how to do it... that is what i am following and it shows me that in the book too

well i do understand what you did to solve the problem... and i did find the answer... its just that all this stuff im looking at is sqrt everything that's all and i didn't see you do that

well C says AX is less than BX2 and it is so i thought it would be that one.

that makes better sense now thank you

constant sorry :(

I got the pH how do i turn that into (H+)

BaSO4 less soluble so answer D

well are you dr. bob can i ask you some questions... kinda like an interview

ok well here is what i have gotten so far: H2O: 1.118 mol C2O4: .58681 mol Fe 3+: .2025 mol K^+: .3862 mol That is what ive gotten doing 20.14 g(1 mol / 18 g) = 1.118 mol and so on with the rest of them Did i do that wrong

ok i did all the mols of those numbers and came out with H2O = (20.51/18.051)=1.136 C2O4 = (52.60/88.016)=.5976 Fe 3+ = (11.55/55.845)= .2068 K + = (15.34/39.098)=.3923 Ive gotten that far... now im a little confused on how you do the rest of the question...

1.136/.2068=5.5 .5976/.2068= 2.88 so 3 .2068/.2068 = 1 .3923/.2068 = 1.89 so 2 now do i do it to all four with different denominators like 1.136/1.136= 1 .5976/1.136 = and so on or do i do it by just that one

well then the question asks later on what the theoretical explanation would be so you choose A or D could the theoretical explanation be one of those and then the experimental be the other

is the answer C

Then A because its going from 0 to +2

would it be A because it is going from Zn to Zn^+2

never mind that wouldnt be right i was looking at the wrong thing

well it cant be A or C so i think that it would be B

I left out this with the problem Ni2+(aq) + 2e¨C ¡ú Ni(s) ¨C0.25 V Sn4+(aq) + 2e¨C ¡ú Sn2+(aq) +0.15 V Br2(l) + 2e¨C ¡ú 2Br¨C(aq) +1.07 V so it says: Which process represents a general method for the preparation of a metal from its compounds? . (A) neutra...

Ni2+(aq) + 2e¨C ¡ú Ni(s) ¨C0.25 V Sn4+(aq) + 2e¨C ¡ú Sn2+(aq) +0.15 V Br2(l) + 2e¨C ¡ú 2Br¨C(aq) +1.07 V

what do you mean by plated

I know that the electrons float over to the cataod SO i think it would be C

2Fe3+ + Sn2+ ¡ú 2Fe2+ + Sn4+ +0.62 V Sn2+ + I2 ¡ú Sn4+ + 2I¨C +0.38 V

man this sucks well hold on 2Fe3+ + Sn2+ --> 2Fe2+ + Sn4+ +0.62 V Sn2+ + I2 --> Sn4+ + 2I– +0.38 V i hope this is better

is an electrode through which (positive) electric current flows into a polarized electrical device

ok i found how to do the surface area but i still don't know what to use for the lateral area

i don't get lateral area either

i don't have the height would i use 82 the slanted side

is the answer 5 thats what i got

banished the daimyo from japan

How did the region's geography affect Kush? Its A. I hope this was helpful for yall ;)