Answer:
E²⁺
Explanation:
The group two contain alkaline earth metals.
There are six elements in group 2A.
Beryllium, Magnesium, calcium, strontium, barium and radium.
All members have two valance electrons.
They lose two valance electrons to complete the octet.
When they lose the two valance electrons they form cation X²⁺.
They react with halogens and form salt such as
MgCl₂, CaCl₂ etc.
Mg²⁺ Cl²⁻₂
The oxidation state of halogens are -1, while the elements of group two A shows +2 that's why two atoms of halogen are combine with one atom of alkaline earth metals and make the compound overall neutral.
All the alkaline earth metals have similar properties.
The answer to this would be false.
B) differences in temperature
Explanation:
The factor that most directly affects the flow of ocean currents is the differences in ocean temperature from one place to another.
Ocean current is the directional movement of the ocean water in its basin.
The main cause of ocean current is differences in temperature.
- Ocean water on the surface receives direct sunlight.
- This warms and the surface and decreases their density.
- When winds blows over them, they cool and sink under their own weight.
- The less cold water in depths rise to replace them.
- This exchange of ocean water due to loss and gain of heat cause ocean current.
learn more:
Ocean density brainly.com/question/6760255
#learnwithBrainly
Answer:
![m=8.79kg](https://tex.z-dn.net/?f=m%3D8.79kg)
Explanation:
First of all we need to calculate the heat that the water in the cooler is able to release:
![Q=\rho * V*Cp*\Delta T](https://tex.z-dn.net/?f=Q%3D%5Crho%20%2A%20V%2ACp%2A%5CDelta%20T)
Where:
- Cp is the mass heat capacity of water
- V is the volume
is the density
![Q=1 g/cm^3 *15000 cm^3*4.184 \frac{J}{g*^{\circ}C}*(10-90)^{\circ}C](https://tex.z-dn.net/?f=Q%3D1%20g%2Fcm%5E3%20%2A15000%20cm%5E3%2A4.184%20%5Cfrac%7BJ%7D%7Bg%2A%5E%7B%5Ccirc%7DC%7D%2A%2810-90%29%5E%7B%5Ccirc%7DC)
![Q=-5020800 J=-5020.8 kJ](https://tex.z-dn.net/?f=Q%3D-5020800%20J%3D-5020.8%20kJ)
To calculate the mass of CO2 that sublimes:
![-Q=\Delta H_{sub}*m](https://tex.z-dn.net/?f=-Q%3D%5CDelta%20H_%7Bsub%7D%2Am)
Knowing that the enthalpy of sublimation for the CO2 is: ![\Delta H_{sub}=571 kJ/kg](https://tex.z-dn.net/?f=%5CDelta%20H_%7Bsub%7D%3D571%20kJ%2Fkg)
![5020.8 kJ=571 kJ/kg*m](https://tex.z-dn.net/?f=5020.8%20kJ%3D571%20kJ%2Fkg%2Am)
![m=\frac{5020.8 kJ}{571 kJ/kg}=8.79kg](https://tex.z-dn.net/?f=m%3D%5Cfrac%7B5020.8%20kJ%7D%7B571%20kJ%2Fkg%7D%3D8.79kg)
Answer: The correct option is C ( is very hard and burns cleanly).
Explanation:
COAL is a form of rock that is made up of mostly carbon amongst other elements which includes sulphur, nitrogen, hydrogen and oxygen. There are different types of coal which include:
--> anthracite ( 90% carbon)
--> bituminous coal ( 70-90% carbon)
--> lignite ( 60- 70% carbon) and
--> peat (60 % carbon).
Anthracite is the type of coal that contains the highest carbon content ( 90% carbon). This makes it very hard and is often a times referred to as HARD COAL. Anthracite is a higher quality coal for domestic and open fire heating. This is because it contains less impurities than other type of coal and thereby making it to BURN CLEANLY avoiding atmospheric pollution.