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3 years ago

Had beryllium and calcium already been discovered

Chemistry

1 answer:

Lina20 [59]3 years ago

3 0

Answer:

Yes

Beryllium is a chemical element with the symbol Be and atomic number 4. It is a steel-gray, strong, lightweight and brittle alkaline earth metal. ... Notable gemstones high in beryllium include beryl (aquamarine, emerald) and chrysoberyl.

Calcium is a mineral that is necessary for life. In addition to building bones and keeping them healthy, calcium enables our blood to clot, our muscles to contract, and our heart to beat. About 99% of the calcium in our bodies is in our bones and teeth.

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A medicine is given 73 grains ap/lbs. of patient per dose. The patient weighs 65.7 kilograms. how many drams ap should the apoth

erastova [34]

10,573.4

Explanation:

Given parameters:

Dosage per patient = 73ap/lbs

Weight of patient = 65.7kg

Unknown:

Amount of grams/ap to be given to the patient;

Solution:

Since our final answer should be expressed in grams, let us convert all units into grams.

1000g = 1kg

Converting 65.7kg to g = 65.7 x 1000 = 65700g

73ap/lbs;

1lb = 453.6g

73ap/lbs x $\frac{1lb}{453.6g}$ = 0.161ap/g

Now,

For a 65700g person, the number of grains app required;

65700 x 0.161 = 10,573.4grains ap per dose

learn more:

Mass brainly.com/question/3764212

#learnwithBrainly

3 0

3 years ago

The activation energy for a reaction is the energy difference between what two components of a reaction?

lora16 [44]

Answer:

Activation Energy is the Energy that Must be Overcome/reached by Reactants for Products to be formed.

I'd go with the 2nd Option.

4 0

3 years ago

The enzyme phosphohexose isomerase catalyzes the interconversion glucose 6-phosphate and fructose 6-phosphate. Given that the ΔG

____ [38]

Answer:

The correct answer is option D.

Explanation:

The chemical equation for the conversion follows:

$\text{ glucose 6-phosphate}\rightleftharpoons \text{fructose 6-phosphate}$

The expression for $K_{eq}$ of above equation is:

$K_{eq}=\frac{\text{[fructose 6-phosphate]}}{\text{[glucose 6-phosphate]}}$

$\Delta G^o=-RT\ln K_[eq}$

where,

$\Delta G^o$ = standard Gibbs free energy = 1.72 kJ/mol = 1720 J/mol (Conversion factor: 1kJ = 1000J)

R = Gas constant = $8.315J/K mol$ (given)

T = temperature =298K

Putting values in above equation, we get:

$1720 J/mol=-(8.315J/Kmol)\times 298K\times \ln (\frac{\text{[fructose 6-phosphate]}}{\text{[glucose 6-phosphate]}})$

$\frac{\text{[fructose 6-phosphate]}}{\text{[glucose 6-phosphate]}}=0.499\approx = 0.5=\frac{1}{2}$

$\frac{\text{[fructose 6-phosphate]}}{\text{[glucose 6-phosphate]}}=\frac{1}{2}$

The ratio of glucose 6-phosphate to fructose 6-phosphate at equilibrium :

$\frac{\text{[glucose 6-phosphate]}}{\text{[fructose 6-phosphate]}}=\frac{2}{1}$

3 0

3 years ago

What causes winter in the Northern Hemisphere? Choose all that apply.

Mandarinka [93]

Option D : The northern hemisphere is tilted away from the sun.

8 0

2 years ago

Read 2 more answers

Determine the mass in grams of potassium chloride that must be added to 97 g of water to make a 1.09 m solution. Enter your answ

miv72 [106K]

Answer: 7.88 grams

Explanation:

Molality of a solution is defined as the number of moles of solute dissolved per kg of the solvent.

$Molarity=\frac{n}{W_s}$

where,

n = moles of solute

$W_s$ = weight of solvent in kg

moles of solute = $\frac{\text {given mass}}{\text {molar mass}}=\frac{xg}{74.5g/mol}$

mass of solvent = 97 g = 0.097 kg (1kg=1000g)

Now put all the given values in the formula of molality, we get

$1.09=\frac{x}{74.5g/mol\times 0.097kg}$

$x=7.88g$

Therefore, the mass in grams of potassium chloride that must be added to 97 g of water to make a 1.09 m solution is 7.88

6 0

3 years ago