Q.2. How does the valency of elements vary in going down a group of the periodic table?

Use the Gizmo to estimate the age of each of the objects below. For these questions, each second in the Gizmo represents 1,000 y

ziro4ka [17]

Answer:

Check the explanation

Explanation:

AT = A0 e(-T/H)

... where A0 is the starting activity, AT is the activity at some time T, and H is the half-life, in units of T.

Substituting what we know, we get...

0.71 = (1) e(-T/5730)

Solve for T...

loge(0.71) = -T/5730

T = -loge(0.71)(5730)

T = 1962 (conservatively rounded, T = 2000)

similarly for all

for aboriginal charcoal

0.28 = (1) e(-T/5730)

Solve for T...

loge(0.28) = -T/5730

T = -loge(0.28)(5730)

T = 7294 (conservatively rounded, T = 7000)

for mayan headdress

0.89 = (1) e(-T/5730)

Solve for T...

loge(0.89) = -T/5730

T = -loge(0.89)(5730)

T = 667 (conservatively rounded, T = 700)

for neanderthal

0.05 = (1) e(-T/5730)

Solve for T...

loge(0.05) = -T/5730

T = -loge(0.05)(5730)

T = 17165 (conservatively rounded, T = 17000)

7 0

2 years ago

In the PhET simulation window, click the radio button labeled Mystery in the Blocks menu on the right-hand side of the screen. U

Yuliya22 [10]

Answer:

B, D, E, C, A

Explanation:

We have 5 blocks with their respective masses and volumes.

Block Mass Volume

A 65.14 kg 103.38 L

B 0.64 kg 100.64 L

C 4.08 kg 104.08 L

D 3.10 kg 103.10 L

E 3.53 kg 101.00 L

The density (ρ) is an intensive property resulting from dividing the mass (m) by the volume (V), that is, ρ = m / V

ρA = 65.14 kg / 103.38 L = 0.6301 kg/L

ρB = 0.64 kg / 100.64 L = 0.0064 kg/L

ρC = 4.08 kg / 104.08 L = 0.0392 kg/L

ρD = 3.10 kg / 103.10 L = 0.0301 kg/L

ρE = 3.53 kg / 101.00 L = 0.0350 kg/L

The order from least dense to most dense is B, D, E, C, A

4 0

2 years ago

Assume an original volume of blood of one deciliter (100 ml). if 5 ml of oxygen diffuses into the blood, what would be its final

oksano4ka [1.4K]

Assume an original volume of blood of one deciliter (100 ml). if 5 ml of oxygen diffuses into the blood, 100 ml will be its final volume.

A tissue is made up of white blood cells, platelets, red blood cells, and other elements suspended in a liquid. Blood transports waste away and delivers nutrients and oxygen to the tissues. The entire amount of fluid moving through the heart's arteries, capillaries, veins, venules, and chambers is referred to as blood volume. Red blood cells (erythrocytes), white blood cells (leukocytes), platelets, and plasma are the elements that give blood volume.

The amount of water and sodium ingested, expelled by the kidneys into the urine, and lost through the digestive system, lungs, and skin determines blood volume. The amounts of salt and water that are consumed and excreted vary greatly.

To know more about blood volume refer to: brainly.com/question/7313563

#SPJ4

5 0

1 year ago

Consider the reaction: 2 H2O (g)-->2 H2 (g) + O2 (g). ΔH=483.6 Kj/mol. If 2 moles of H2O (g) are converted H2(g) and O2(g) ag

denis-greek [22]

DE = dH - PdV

2 H2O(g) → 2 H2(g) + O2(g) 

You can see that there are 2 moles of gas in the reactants and 3 moles of gas in the products. 

1 moles of ideal gas occupies the same volume as 1 mole of any other ideal gas under the same conditions of temp and pressure. 

Since it is done under constant temp and pressure that means the volume change will be equal to the volume of 1 mole of gas 

2 moles reacts to form 3 moles 

The gas equation is 

PV = nRT 
P = pressure 
V = volume (unknown) 
n = moles (1) 
R = gas constant = 8.314 J K^-1 mol^-1 
- the gas constant is different for different units of temp and pressure (see wikki link) in this case temp and pressure are constant, and we want to put the result in an equation that has Joules in it, so we select 8.314 JK^-1mol^-1) 
T = temp in Kelvin (kelvin = deg C + 273.15 
So T = 403.15 K 

Now, you can see that PV is on one side of the equation, and we are looking to put PdV in our dE equation. So we can say 

dE = dH -dnRT (because PV = nRT) 

Also, since the gas constant is in the unit of Joules, we need to convert dH to Joules 

dH = 483.6 kJ/mol = 483600 Joules/mol 

dE = 483600 J/mol - (1.0 mol x 8.314 J mol^-1K-1 x 403.15 K) 
dE = 483600 J/mol - 3351.77 J 
dE = 480248.23 J/mol 
dE = 480.2 kJ/mol

5 0

2 years ago

Read 2 more answers

An analytical chemist weighs out 0.093g of an unknown monoprotic acid into a 250mL volumetric flask and dilutes to the mark with

Kamila [148]

Answer:

The molar mass of the unknown acid is 89 g/mol

Explanation:

Step 1: The balanced equation

HA(aq) + NaOH(aq) → NaA(aq) + H2O(l)

It takes 1 mole of NaOH to neutralize 1 mole of the triprotic acid. This is called the reaction stoichiometry.

Step 2: Data given

Mass of the acid = 0.093 grams

volume = 250 mL

titrates with 0.16 M NaOH

adds 6.5 mL NaOH

Step 3: Calculate moles of NaOH

We know the concentration and volume of NaOH needed to neutralize the acid.

By determining the moles of NaOH in that volume in liters (95.9mL=0.0959L), the moles of acid in the original sample can be determined from the reaction stoichiometry.

Moles = Molarity * Volume

Moles = 0.16 M * 0.0065 L

Moles = 0.00104 moles NaOH

Step 4: Calculate moles of the unknown acid:

It takes 1 mole of NaOH to neutralize 1 mole of the triprotic acid. This is called the reaction stoichiometry.

For 0.00104 moles NaOH we have 0.00104 moles of HA

Step 5: Calculate the molar mass of the acid

Molar mass Ha = Mass Ha / moles Ha

Molar mass Ha = 0.093 grams / 0.00104 moles

Molar mass Ha = 89.42 g/mol ≈89 g/mol

The molar mass of the unknown acid is 89 g/mol

3 0

2 years ago

Q.2. How does the valency of elements vary in going down a group of the periodic table?​

Q.2. How does the valency of elements vary in going down a group of the periodic table?