All categories

3 years ago

Who did Churchill and Roosevelt appoint to lead the Normandy invasion?

Chemistry

2 answers:

Anna71 [15]3 years ago

5 0

First this aint chemistry second it's DWIGHT D. EISENHOWER
i gotchu

aivan3 [116]3 years ago

4 0

Churchill and Roosevelt appointed Dwight d. Eisenhower to lead the Normandy invasion.

Final Answer: Dwight d. Eisenhower

You might be interested in

A simple definition of cells

Stolb23 [73]

Answer:

Cells are the basic structural and functional unit of life.

5 0

2 years ago

frez [133]

Answer:

See explanation

Explanation:

When a beaker of ethanoic acid is placed in the refrigerator, its temperature drops and the vessel feels cool.

Now, when we mix ethanoic acid and sodium carbonate, an endothermic reaction occurs, fizzing is observed as carbon dioxide is given off and heat is lost to the surroundings causing the reaction vessel to feel cool to touch.

The difference between putting ethanoic acid in the refrigerator and adding sodium carbonate to the solution is that, in the former, no new substance is formed. The substance remains ethanoic acid when retrieved from the refrigerator. In the later case, new substances are formed. The substance is no more ethanoic acid because a chemical reaction has taken place.

5 0

2 years ago

Which best explains why water is able to “stick” to the side of glass?

AveGali [126]

Explanation:

Adhesion means the ability to stick on the surface of another substance.

Water exhibits adhesive forces due to which it is able to stick to the glass. Due to adhesive forces water spreads over the surface of glass and sticks to it.

These adhesive forces between the glass and water enough that it deforms the spherical shape of water molecules and help them stick to the surface of glass. As a result, adhesive forces overcome the repulsion between like molecules.

Hence, water is able to “stick” to the side of glass due to strong adhesive forces.

4 0

3 years ago

Read 2 more answers

Blank are produced when atoms if the elements in group 7A blank an electron

Romashka [77]

Answer:

Halide ions are produced when atoms of elements in Group 7A gain an electron.

Explanation:

6 0

3 years ago

Write packing efficiency of fcc ,BCC, SCC and formula also . ?

Minchanka [31]

❖ Packing Efficiency ❖

➪ The percentage of total space occupied by particles is called packing efficiency.

$\\ \qquad{\rule{200pt}{3pt}}$

$\bigstar \boxed{ \sf \: \bigg(Packing \; effeciency = \dfrac{Total \; value \; of \; sphere}{Volume \; of \; unit \; cell} \times 100 \bigg)}$

❖ Packing efficiency of simple cubic structure (SCC).❖

$\rm \: {Let \: } \bf{r } \: \rm{ be \: the \: radius \: of \: a \: sphere }\: \\ \rm and \: \bf{a} \: \rm {be \: the \: edge \: of \: unit \: cell.} \\ \\ \; \bigstar \boxed{ \sf{Volume_{(sphere)} = \dfrac{4}{3} \pi r^3}} \bigstar$

❒ Since, simple cubic unit cell contain 1 atom (sphere). So, the total volume of sphere will be :

$: : \implies \sf \: 1 \times \dfrac{4}{3}\pi r^3 = \dfrac{4}{3}\pi r^3$

Volume of unit cell = a³

Volume of unit cell = (2r)³

Volume of unit cell = 8r³

❒ Now, we know that,❒

$\bigstar \boxed{ \sf \: \bigg(Packing \; effeciency = \dfrac{Total \; value \; of \; sphere}{Volume \; of \; unit \; cell} \times 100 \bigg)}$

➪ Substituting the known values in the formula, we get the following results:

$: : \implies \rm \: {\dfrac{\dfrac{4}{3}\pi r^3}{8r^3} \times 100} \\ \\ : : \implies \dfrac{\pi}{6} \times 100 \\\\\ : : \implies \bf {52.4 \%}$

❒ Hence, the packing efficiency of simple cubic structure is 52.4%.

$\\ \qquad{\rule{200pt}{3pt}}$

➪ Packing efficiency of cubic close packing (SCC)/face centred cubic structure (FCC).

❒ Since, simple cubic unit cell contain 2 atom (sphere). So, the total volume of sphere will be:

$: : \implies \rm 4 \times \dfrac{4}{3}\pi r^3 = \dfrac{16}{3}\pi r^3$

Volume of unit cell = a³

Volume of unit cell = (2√2r)³

Volume of unit cell = 16√2r³

❒ Now, we know that,❒

$\bigstar \boxed{ \sf \: \bigg(Packing \; effeciency = \dfrac{Total \; value \; of \; sphere}{Volume \; of \; unit \; cell} \times 100 \bigg)}$

➪Substituting the known values in the formula, we get the following results:

$: : \implies \rm {\dfrac{\dfrac{16}{3}\pi r^3}{16\sqrt{2}r^3} \times 100 }\\\\ \implies \rm \dfrac{\pi}{3\sqrt{2}} \times 100 \\\\\ \implies\bf52.4 \%$

❖ Hence, the packing efficiency of face centred cubic structure is 74%.

$\\ \qquad{\rule{200pt}{3pt}}$

❖ Packing efficiency of body cubic structure (BCC).

❒ Since, simple cubic unit cell contain 2 atom (sphere). So, the total volume of sphere will be:

$: : \implies \rm \: 2 \times \dfrac{4}{3}\pi r^3 = \dfrac{8}{3}\pi r^3$

Volume of unit cell = a³

Volume of unit cell = (4r/√3)³

Volume of unit cell = 64r³/3√3

❒ Now, we know that,❒

$\bigstar \boxed{ \sf \: \bigg(Packing \; effeciency = \dfrac{Total \; value \; of \; sphere}{Volume \; of \; unit \; cell} \times 100 \bigg)}$

➪Substituting the known values in the formula, we get the following results:

$: : \implies \rm {\dfrac{\dfrac{8}{3}\pi r^3}{\dfrac{64r^3}{3\sqrt{3}}} \times 100} \\\\ \implies \dfrac{3\pi}{8} \times 100 \\\ \\ \bf \implies \: 68 \%$

❒ Hence, the packing efficiency of body centred cubic structure is 68%.

$\\ \qquad{\rule{200pt}{3pt}}$

6 0

2 years ago