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4 years ago

BRAINILY ANSWER NOW OLEASE I NEED HELP

Chemistry

2 answers:

UNO [17]4 years ago

8 0

Answer:

From Earth, the Sun looks like it moves across the sky in the daytime and appears to disappear at night. This is because the Earth is spinning towards the east. The Earth spins about its axis, an imaginary line that runs through the middle of the Earth between the North and South poles.

Explanation:

natali 33 [55]4 years ago

5 0

Answer:

The Earth rotates on its axis always, so it looks like the sun is moving but it is the Earth that's moving.

Explanation:

Hope this helps!

You might be interested in

Según la Organización Mundial de la Salud, el nitrato de plata ( densidad = 4.35 g/cc ) es una sustancia con propiedades cáustic

OlgaM077 [116]

Answer:

737.52 mL de agua

Explanation:

En este caso solo debes usar la expresión de molaridad de una solución la cual es:

M = moles / V

Donde:

V: Volumen de solución.

Como queremos saber la cantidad de agua, queremos saber en otras palabras cual es la cantidad de solvente que se utilizó para preparar los 800 mL de disolución.

Una disolución se prepara con un soluto y solvente. El soluto lo tenemos, que es el nitrato de plata. Con la expresión de arriba, calculamos los moles de soluto, y luego su masa. Posteriormente, calculamos el volumen con la densidad, y finalmente podremos calcular el solvente de esta forma:

V ste = Vsol - Vsto

Primero calcularemos los moles de soluto:

moles = M * V

moles = 2 * 0.800 = 1.6 moles

Con estos moles, se calcula la masa usando el peso molecular reportado que es 169.87 g/mol:

m = moles * PM

m = 1.6 * 169.87 = 271.792 g

Ahora usando el valor de la densidad, calcularemos el volumen de soluto empleado:

d = m/V

V = m/d

V = 271.792 / 4.35

V = 62.48 mL

Finalmente, la cantidad de agua necesaria es:

V agua = 800 - 62.48

V agua = 737.52 mL

8 0

4 years ago

True or false ? <br>an insoluble base will react with an acid. <br>

Leno4ka [110]

Answer:

true maybe

Explanation:

#CarryOnLearning

7 0

3 years ago

Enter your answer in the provided box.S(rhombic) + O2(g) → SO2(g) ΔHo rxn= −296.06 kJ/molS(monoclinic) + O2(g) → SO2(g) ΔHo rxn=

IgorC [24]

Answer: $\Delta H^0=+0.3kJ/mol$ .

Explanation:

According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.

According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.

$S_{rhombic}+O_2(g)\rightarrow SO_2(g)$ $\Delta H^0_1=-296.06kJ$ (1)

$S_{monoclinic}+O_2(g)\rightarrow SO_2(g)/tex] [tex]\Delta H^0_2=-296.36kJ$ (2)

The final reaction is:

$S_{rhombic}\rightarrow S_{monoclinic}$ $\Delta H^0_3=?$ (3)

By subtracting (1) and (2)

$\Delta H^0_3=\Delta H^0_1-\Delta H^0_2=-296.06kJ-(-296.36kJ)=0.3kJ$

Hence the enthalpy change for the transformation S(rhombic) → S(monoclinic) is 0.3kJ

3 0

3 years ago

Calculate the freezing temperature of the following solution of 0.50 M glucose (a covalent compound). Assume that the molality o

kirza4 [7]

Answer:

-0.93 °C

Explanation:

Hello,

The freezing-point depression is given by:

$T_f-T_f^*=-iK_{solvent}m_{solute}$

Whereas $T_f$ is the freezing temperature of the solution, $T_f^*$ is the freezing temperature of the pure solvent (0 °C since it is water), $i$ the Van't Hoff factor (1 since the solute is covalent), $K_{f,solvent}$ the solvent's freezing point depression point constant (in this case $1.86 C\frac{kg}{mol}$ ) and $m_{solute}$ the molality of the glucose.