Ask question

Ask question

All categories

2 years ago

13

How much heat is required to increase the temperature of 10.0 grams of water 6.0oC? (The specific heat of water is 4.18 J/g x oC

)

1 answer:

Paraphin [41]2 years ago

5 0

250.8 J

Approximately 250 J (A on Plato)

You might be interested in

Assuming that the experiments performed in the absence of inhibitors were conducted by adding 5 μl of a 2 mg/ml enzyme stock sol

prohojiy [21]

Hey there!:

From the given data ;

Reaction volume = 1 mL , enzyme content = 10 ug ( 5 ug in 2 mg/mL )

Enzyme mol Wt = 45,000 , therefore [E]t is 10 ug/mL , this need to be express as "M" So:

[E]t in molar = g/L * mol/g

[E]t = 0.01 g/L * 1 / 45,000

[E]t = 2.22*10⁻⁷

Vmax = 0.758 umole/min/ per mL

= 758 mmole/L/min

=758000 mole/L/min => 758000 M

Therefore :

Kcat = Vmax/ [E]t

Kcat = 758000 / 2.2*10⁻⁷ M

Kcat = 3.41441 *10¹² / min

Kcat = 3.41441*10¹² / 60 per sec

Kcat = 5.7*10¹⁰ s⁻¹

Hence kcat of xyzase is 5.7*10¹⁰ s⁻¹

Hope that helps!

4 0

2 years ago

how many moles of cesium carbonate will be produced when 5.34 moles of cesium reacts with iron iii carbonate

irga5000 [103]

Answer: 2.7moles

Explanation:

6Cs + Fe2(CO3)3 —> 3Cs2CO3 + 2Fe

From the equation,

6moles of Cs produced 3 moles of Cs2CO3.

Therefore, 5.34 moles of Cs will produce = (5.4x3)/6 = 2.7moles of Cs2CO3

6 0

2 years ago

The volume of a gas is 36.0 ml at 10.0°c and 4.50 atm. at what temperature (°c) will the gas have a pressure of 3.50 atm and a v

galben [10]

Using the combined gas law, where PV/T = constant, we first solve for PV/T for the initial conditions: (4.50 atm)(36.0 mL)/(10.0 + 273.15 K) = 0.57213.
Remember to use absolute temperature.
For the final conditions: (3.50 atm)(85.0 mL)/T = 297.5/T
Since these must equal, 0.57213 = 297.5/T
T = 519.98 K
Subtracting 273.15 gives 246.83 degC.

5 0

1 year ago

The density of o2 gas at 16 degrees Celsius and 1.27atm is?

velikii [3]

Answer:

The density of O₂ gas is 1.71 $\frac{g}{L}$

Explanation:

Density is a quantity that allows you to measure the amount of mass in a given volume of a substance. So density is defined as the quotient between the mass of a body and the volume it occupies:

$density=\frac{mass}{volume}$

An ideal gas is characterized by three state variables: absolute pressure (P), volume (V), and absolute temperature (T). The relationship between them constitutes the ideal gas law, an equation that relates the three variables if the amount of substance, number of moles n, remains constant and where R is the molar constant of the gases:

P * V = n * R * T

So, you can get:

$\frac{n}{V} =\frac{P}{R*T}$

The relationship between number of moles and mass is:

$n=\frac{mass}{molar mass}$

Replacing:

$\frac{\frac{mass}{molar mass} }{V} =\frac{P}{R*T}$

$\frac{mass}{V*Molar mass} =\frac{P}{R*T}$

So:

$\frac{mass}{V} =\frac{P*molar mass}{R*T}$

Knowing that 1 mol of O has 16 g, the molar mass of O₂ gas is 32 $\frac{g}{mol}$ .

Then:

$\frac{mass}{V} =\frac{P*molar mass of O_{2} }{R*T}$

In this case you know:

P=1.27 atm
molar mass of O₂= 32 $\frac{g}{mol}$ .

R= 0.0821 $\frac{atm*L}{mol*K}$

T= 16 °C= 289 °K (0°C= 273°K)

Replacing:

$density=\frac{mass}{V} =\frac{1.27atm*32\frac{g}{mol} }{0.0821\frac{atm*L}{mol*K} *289 K}$

Solving:

density= 1.71 $\frac{g}{L}$

<u><em>The density of O₂ gas is 1.71 </em></u> $\frac{g}{L}$ <u><em></em></u>

3 0

2 years ago

When double-stranded DNA is heated at neutral pH, which change does not occur?

Sindrei [870]

Answer:

B) The covalent N-glycosidic bond between the base and the pentose breaks

Explanation:

When forces that bind 2 DNA strands are broken, these strands finally split. This process is called denaturalization

The main forces that remain both DNA strands together are the hydrogen bonds (physical forces), between pair of bases (Adenine with Thymine, and Guanine with Cytosine)

Denaturalization may occur by different factor: Ph alteration, salt addition, temperature (heating), etc

When heating a DNA solution, denaturalization process may be followed using UV absorption (normally, at wavelength of 260 nm): when DNA (double strand) has its regular structure, UV light absorption is low, as the nitrogen bases are stacked like a pile of coins, for which structure absorbs less light

When DNA structure is denaturalized, these nitrogen bases are exposed, and UV absorption increases

Also, DNA denaturalization may be followed by viscosity: for a double strand DNA solution, viscosity is high due to double chain stiffness but when strands are denaturalized, simple strands solution are less viscous (so viscosity decreases over time, when heating the solution)

Lastly, when solution is heated, only physical forces are broken (hydrogen bonds) and not chemical bonds (such as covalent bonds), for which extreme conditions are needed

7 0

1 year ago