What can the size and shape of a sand dune tell you about how it was formed?

I’m having trouble with this assignment please help.

shutvik [7]

Q = m.c.AT

m = 50,0 g of iron

c = 0.450 J.g-1°C-1

AT = 10°C

Thus

Q = 50 * 0.450 * 10

Q = 225 J

Is the heat energy

Hope it helps xx

3 0

4 years ago

What is the empirical formula of the mineral Co+Fe+As

dlinn [17]

Answer:

(Co,Fe)As2

Explanation:

The formula of the mineral safflorite, a compound made of cobalt, iron, and arsenic is (Co,Fe)As2. This itself is the imperical formula, it cannot be divided any further

6 0

3 years ago

Explain why the pressure in a sealed container of gas decreases when heat is added to the system?

weeeeeb [17]

Answer:

the question is bogus

see explanation

Explanation:

explain why the pressure in a sealed container of gas decreases when heat is added to the system?

when you add heat to the gas molecules in a sealed container, the molecules move faster and the pressure INCREASES!!!

IT DOES NOT DECREASE

PV =nrT

IF THE O THEVOLUME IS FIXED (REIN A SEALED CONTAINER) AND THE NUMBER OF MOLES n is FIXED, THEN THE PRESSURE IS DIRECTLY PROPORTIONAL THE TEMPERATURE

THE GREATER T, THE GREATER P

4 0

3 years ago

Consider the following unbalanced chemical equation. C5H12(l) + O2(g) → CO2(g) + H2O(l) If 21.9 grams of pentane (C5H12) are bur

Marina CMI [18]

Answer : The mass of water produced will be 32.78 grams.

Explanation : Given,

Mass of $C_5H_{12}$ = 21.9 g

Molar mass of $C_5H_{12}$ = 72.15 g/mole

Molar mass of $H_2O$ = 18 g/mole

First we have to calculate the moles of $C_5H_{12}$ .

$\text{Moles of }C_5H_{12}=\frac{\text{Mass of }C_5H_{12}}{\text{Molar mass of }C_5H_{12}}=\frac{21.9g}{72.15g/mole}=0.3035moles$

Now we have to calculate the moles of $H_2O$ .

The balanced chemical reaction will be,

$C_5H_{12}(l)+8O_2(g)\rightarrow 5CO_2(g)+6H_2O(l)$

From the balanced reaction we conclude that

As, 1 mole of $C_5H_{12}$ react to give 6 moles of $H_2O$

So, 0.3035 moles of $C_5H_{12}$ react to give $0.3035\times 6=1.821$ moles of $H_2O$

Now we have to calculate the mass of $H_2O$ .

$\text{Mass of }H_2O=\text{Moles of }H_2O\times \text{Molar mass of }H_2O$

$\text{Mass of }H_2O=(1.821mole)\times (18g/mole)=32.78g$

Therefore, the mass of water produced will be 32.78 grams.

3 0

3 years ago

Which trend is observed as the first four elements in group 17 on the periodic table are considered in order of increasing atomi

s344n2d4d5 [400]

ANSWER:

The melting and boiling points increase in order of increasing atomic number.

The size of the nucleus increases in order of increasing atomic number.

Ionization energy decreases in order of increasing atomic number.

Electronegativity decreases in order of increasing atomic number.

Electron Affinity decreases in order of increasing atomic number.

The reactivities decrease in order of increasing atomic number.

EXPLANATION:

NAME MELTING POINT BOILING POINT

Fluorine -220 -188

Chlorine -101 -35

Bromine -7.2 58.8

Iodine 114 184

Melting and Boiling points increase as shown above.

NAME COVALENT RADIUS IONIC RADIUS

Fluorine 71 133

Chlorine 99 181

Bromine 114 196

Iodine 133 220

Size increases as shown above.

NAME FIRST IONIZATION ENERGY

Fluorine 1681

Chlorine 1251

Bromine 1140

Iodine 1008

Ionization energy decreases as shown above.

NAME ELECTRONEGATIVITY

Fluorine 4

Chlorine 3

Bromine 2.8

Iodine 2.5

Electronegativity decreases as shown above.

NAME ELECTRON AFFINITY

Fluorine -328.0

Chlorine -349.0

Bromine -324.6

Iodine -295.2

Electron affinity decreases as shown above.

REACTIVITY

The reactivities of the halogens decrease. This is due to the fact that atomic radius increases in proportion with an increase of electronic energy levels. This decreases the pull for valence electrons of other atoms, minimizing reactivity.

6 0

3 years ago