Answer:
The temperature of the cold water is lower than the warm one. So, when we put the hand in the warm from the cold water, our hand will absorb heat, causing the hand to feel hot. Thus, we can conclude that the more heat it absorbs, the more hotter it is. Whereas the more heat it releases, the colder it is.
Answer : 9773 kJ
Explanation:
Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and
for the reaction comes out to be negative.
To calculate the moles :

Given : Change in enthalpy on combustion of 1 mole of methanol = -1278 kJ
According to stoichiometry :
1 mole of methanol produce energy = 1278 kJ
Thus 7.647 moles of methanol produce energy =
Thus 9773 kJ of energy is produced from burning 245.0 g of methanol in excess oxygen
Answer:
B.Carbohydrates and D. water
The frequency of radiation : 1.2 x 10¹⁵ Hz
<h3>Further explanation
</h3>
Radiation energy is absorbed by photons
The energy in one photon can be formulated as

Where
h = Planck's constant (6,626.10⁻³⁴ Js)
f = Frequency of electromagnetic waves
<h3>f = c / λ
</h3>
c = speed of light
= 3.10⁸ m/s
λ = wavelength
Wavelength-λ is 2.51 x 10⁻⁷m
The frequency :

El valor de la presión osmótica que corresponde a una solución que contiene 2 moles de soluto en un litro de solución a una temperatura de 17°C es 47.56 atmósferas.
La presión osmótica se puede calcular usando la siguiente ecuación:
(1)
En donde:
n: es el número de moles = 2 moles
R: es la constante de los gases = 0.082 L*atm/(K*mol)
T: es la temperatura = 17 °C = 290 K
V: es el volumen = 1 L
Introduciendo lo valores anteriores en la ecuación (1), tenemos:
Por lo tanto, la presión osmótica es 47.56 atmósferas.
Puedes encontrar más aca:
Espero que te sea de utilidad!